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Texas Basketball, Inside the Numbers: The Missing Offensive Rebounds

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Jarrett Allen and Shaq Cleare have been tremendous on the offensive glass. But their teammates haven’t given them very much help.

NCAA Basketball: Oklahoma at Texas
You can’t blame Cleare and Allen for Texas’ problems getting second shots.
Brendan Maloney-USA TODAY Sports

The 2016-2017 Texas Longhorns basketball season is nearing the end of January, and the Texas still has struggles scoring. Over the last few weeks, we have gone over many of the various issues with a Texas offense that currently ranks last in the Big 12 in points per possession during league games.

While earlier in the season the Longhorns struggled with shot making, that hasn’t exactly been the case as of late for Texas. The ‘Horns are currently shooting the ball at 34 percent from three-point range and 50 percent from inside the arc in conference play, which while not stellar suggests that Texas is starting to get some shots to fall. All in all, it isn’t dragging the offense down very much at the moment.

For any Texas fan who has watched the games lately, another problem will probably first come to mind — turnovers. The Longhorns are currently turning the ball over in 23 percent of possessions during Big 12 games, which ranks ninth in the conference. I have recently looked at where these turnovers are coming from, so today I want to focus on something else.

There is another problem eating at the Texas offense — one that is a little bit harder to see while watching the games. It is harder to spot because it is something that isn’t happening, which makes it more difficult to pick up on without looking at the numbers.

Beating opponents by attempting more shots

If there is one theme I have touched on more than any other over the six seasons that I have been writing about Texas basketball, it is that the ability of a team to consistently get more shots than its opponents in games makes winning much easier.

This statement, in a nutshell, describes the career of Bob Huggins. When I first started writing at BON, I used to go through every game and compare the total number of shots attempted by Texas with the number of shots attempted by Longhorn opponents. I finally grew tired of this, but that doesn’t mean that shot differentials stopped being important.

The table below shows Texas’ field-goal attempt differential and free-throw attempt differential game by game through the first eight games of the Big 12 season. Also shown is something called “Adjusted Shot Difference,” which provides a number that combines field-goal attempts and free-throw attempts in an approximate way.

Shots by game

Game FGA Difference FTA Difference Ajusted Shot Difference
Game FGA Difference FTA Difference Ajusted Shot Difference
At Kansas State 7 -21 -3
Oklahoma State -4 10 1
At Iowa State -14 4 -12
TCU -2 1 -2
West Virginia -4 -9 -8
At Baylor -12 4 -10
At Kansas -1 0 -1
Oklahoma 3 -3 2
AVERAGE -3.4 -1.8 -4

On average, Big 12 opponents have had four more shooting chances per game than the Longhorns so far this season. Texas has only attempted more total shots than its conference opponents twice so far this season. Unsurprisingly, these two games were the only Texas league victories.

When you consistently get fewer shots than your opponents, it means that to win you have to be more efficient than your opponents on a per shot basis to win. For a team like Texas that ranks in the middle of the pack in terms of effective field goal percentage, free-throw percentage, and free-throw rate (a measure of how often a team gets to the free throw line), it just isn’t very easy to be more efficient shooting the ball than opponents.

For the Longhorns, this negative shot differential is being driven by the two things that it always is driven by, turnovers and rebounding. Texas is in ninth place in the Big 12 in turnover rate, as mentioned above, and which you probably already can tell.

But maybe something you cannot tell, but is also true, is that Texas is also ranked ninth in the conference in offensive rebounding rate. During conference games, Shaka Smart’s team is only coming down with 26 percent of the available offensive rebounds. This is simply awful, and is a massive drag on the offense.

How big of a drag is it? Well, we can look at the offensive waterfall chart during Big 12 games to tell just how much of a problem this is.

I have been using these waterfall charts here for a few years, and if you want to read more about the details I suggest starting with this article. In a nutshell, the waterfall chart illustrates how much better or worse a team’s offense is compared with a typical offense that scores 1.04 points per possession by delivering more or less NCAA median-level results in seven statistical categories that define team offensive success. The team of interest can perform better or worse than median in each of these categories, and then by calculating the impact of this difference in each category it is possible to construct the chart above, which shows the cumulative effects of these differences on an offense.

Or, in an even smaller nutshell, big red bars are bad.

The Texas offense in conference games basically has two big red bars. The biggest bar corresponds to turnovers. The second biggest bar relates to offensive rebounding. Both of these factors combine to make it generally likely that the Longhorns will attempt fewer shots in a given game then their opponent. Roughly two-thirds of this problem is caused by turnovers, while the other third is caused by a lack of offensive rebounds.

It is also worth considering that Texas’ two conference wins came in games where the Longhorns did well on the offensive glass and protected the ball. These are the only two conference games where Shaka Smart’s team scored more than one point per possession.

The fact that Texas is doing so poorly on the offensive glass does not seem to be carrying over to the defensive end of the floor. Despite some early issues during the non-conference season, the Longhorns have actually been outstanding on the defensive glass as of late. Texas is currently ranked first in the Big 12 in defensive rebounding rate, allowing opponents to recover their misses 28 percent of the time.

When you consider the teams that the Longhorns have faced include West Virginia, Baylor, and Oklahoma State, this is no small accomplishment. Jarrett Allen is doing a pretty nice job on the defensive glass, and a number of his teammates are helping out there as well.

But this is not a piece about defense. This is about offense. Let’s dive deeper to try to get to the root of Texas’ problems finding second chances to score.

Who is doing the rebounding; revisiting the 2011-2012 season

Followers of Texas basketball spent the better part of two decades watching Texas teams under Rick Barnes that always excelled at going to the offensive glass. Because Texas fans have experience with these teams, they form a great reference point to compare the current unit with to get a better feel of what is missing in terms of generating second chances to score this season.

I could have picked virtually any Texas team under Barnes as an example of a team that was successful on the offensive glass (because they all were), but many of these comparisons probably wouldn’t have been particularly helpful in this setting. That is because many of Barnes’ teams had far more big men then what we see with the present roster.

So instead, I went back and looked at one of the smallest teams that Barnes ever coached. The 2011-2012 featured one regular player who listed at 6’8 or taller (Clint Chapman) and possessed many other features that make it a useful reference point for this team. Like the present group, that squad was also fairly young, running with two seniors who were career role players (Chapman and Alexis Wangmene), a junior (J’Covan Brown), and a bunch of freshmen. But unlike the present team, the 2012 group had a solid season and finished just outside of the top 30 in adjusted offensive efficiency, per kenpom.com. That team’s key advantages over this one were Brown (who was outstanding that season) and offensive rebounding.

The 2011-2012 team tracked down 38 percent of its own misses, compared with with this season’s 28 percent offensive rebounding percentage. That is a difference that is worth a bit more than six points per 100 possessions, or about 4.4 points in a 70 possession game. That is greater than Texas’ margin of defeat against Kansas State, TCU, and West Virginia.

But I didn’t go back and select this prior example team just for the sole purpose of picking on the present one. I picked it because it gives us an example of how a young and mostly undersized team can still be good at rebounding.

The figure below shows how the individual contributions of the major contributors on this season’s team impact team offensive rebounding percentage, and compare it to the 2011-2012 team.

The full size of the bar for each team corresponds to team offensive rebounding percentage, and each individual player’s estimated contribution to that is also indicated. The players are sorted by order of the size of the contribution, with players having the greatest impact appearing at the bottom of each bar. Note that I put this chart together before the Oklahoma game, so it isn’t quite up to date, but at this point in the season missing a single game doesn’t have much of an effect on something like this.

There is a lot to digest in the figure, so let’s start with some basic orientation. Jarrett Allen has the single greatest contribution of any player on either team, which is not surprising at all. Allen has played more than any big man on either team, and has one of the highest individual offensive rebounding rates of any of the listed players.

For each team, players basically sort out into clean positional groupings. I have listed Tevin Mack as a forward in the diagram, simply because he played more minutes in the frontcourt this season than he did on the wing. Perhaps to be more accurate I should have gone back and figured out how Mack rebounded when he was playing as Texas’ four-man, and how he rebounded from the wing, but this would have been a time-consuming exercise that wouldn’t have done much to impact how I end up interpreting the figure.

The four big men for the 2011-2012 team out-rebounded the frontcourt players from this season’s team, but only by a modest amount. This small difference is worth about three percentage points of the 10-point difference between the two squads.

This small difference is surprising given how many frontcourt minutes this year that have gone to Tevin Mack, who simply doesn’t get to offensive rebounds as often as the more traditional big guys. That 2012 squad featured several tremendous offensive rebounders — in particular Jonathan Holmes and Jaylen Bond — and this season’s group, despite being somewhat undermanned, is nearly keeping pace. That speaks highly to the work of Allen and Shaq Cleare.

We have to look at the perimeter player contributions to start to get a better feel for the source of the difference. The contributions of the guards from the 2011-2012 team substantially outpace those of this season’s group. Both Julian Lewis and Sheldon McClellan went to the offensive glass at reasonably high rates for perimeter players, with personal offensive rebounding percentages of seven percent and five percent, respectively. These are good numbers for guards, while a big man like Allen ends up with a number of around 12 percent.

Among Texas’ full-time perimeter players, only Kendal Yancy from this season’s team tops five percent, and Yancy’s impact on the overall team result is limited by playing time. No other full-time Texas perimeter player on this season’s squad has an offensive rebounding percentage of greater than two percent. The only 2011-2012 perimeter player with an offensive rebounding percentage below two percent was Sterling Gibbs, who hardly ever played.

So if you want a quick summation of this section, it is this — this season’s Texas squad isn’t getting much offensive rebounding out of its guards. If this group could collectively track down a few more offensive rebounds per game, it would make a meaningful improvement to the offense.

What is interesting about this is that it stands in contrast to the rebounding at the defensive end, where Texas’ guards are good. Andrew Jones has 75 defensive rebounds this season, second only to team leader Jarrett Allen, and has the third-highest defensive rebounding percentage on the team. He is, by any reasonable measure, an excellent defensive rebounding guard. And Jones isn’t the only one. Kerwin Roach is fourth on the team in total defensive rebounds, and is sporting a defensive rebounding percentage comparable to James Banks and Tevin Mack. Eric Davis has done a good job on the defensive glass as well.

Much of the reason that Texas is ranked so highly in the Big 12 in defensive rebounding is because of the work of its guards (along with the fact that Allen has turned into a monster on the glass during conference play). But on the other end of the floor, they just aren’t coming up with as many balls.

How Texas gets offensive rebounds

We can break down offensive rebounds in a lot of different ways, but one way that I find helpful is to look at rebounding results based on where the rebounded shots were attempted from on the floor.

We can use play-by-play to break down rebounded shot types into four groups: at rim, non-rim twos, threes, and free throws. All four of these shot types tend to generate offensive rebounding opportunities at different rates, and all four tend to produce very different rebounding percentage outcomes.

The table below provides the results for Texas rebounding compared with the various national averages taken through last weekend’s game. There are a lot of data in the table, so let’s go through line by line and understand what is reported.

Offensive rebounding

Category Texas National Average
Category Texas National Average
TOTAL ORB% 28% 30%
% rebounding chances at rim 18% 23%
ORB% at rim 45% 40%
% rebonding chances non-rim 2s 33% 29%
ORB% non-rim 2s 29% 30%
% rebounding chances 3s 38% 38%
ORB% 3s 25% 29%
% rebounding chances FTs 11% 10%
ORB% FTs 8% 13%
Texas’ offensive rebounding results by shot location

The first row is simple. It lists Texas’ overall offensive rebounding percentage (28 percent) as well as the national average (30 percent). The Longhorns are below the national average, but this actually understates the problem the Longhorns are having compared with the rest of the teams of the Big 12. In Big 12 league games so far this season, missed shots are recovered by the offense 33 percent of the time, which is meaningfully higher than the national average and is the highest rate of any conference in D-I.

The next row lists the percentage of total offensive rebounding chances that come on missed shot attempts at the rim. Texas’ result of 18 percent is somewhat lower than the national average. This difference is due to a combination of two factors: the Longhorns take a below-average fraction of their total shot attempts at the rim and make a higher than average percentage of these chances. The combination of these two factors (one good and one bad) is that the Longhorns get fewer opportunities to get offensive rebounds at the rim.

The next row shows Texas’ offensive rebounding percentage on missed shots at the rim, compared with the national average. There are a couple of things to notice here. First, missed shots at the rim are more likely to be recovered by the offense than any other shot. This result makes intuitive sense, as shots taken near the rim frequently draw helping defenders out of weak-side rebounding position, making things easier on the offense. The second fact to notice here is that the Longhorns are actually doing a very solid job of getting offensive rebounds on missed shots attempted at the basket, beating the national average by five percentage points.

This result seems more or less consistent with the offensive rebounding breakdown by player. In general, missed shots attempted near the rim do not rebound as far away from the basket as other missed shots, meaning that they are more likely to be rebounded by the offensive players who play closer to the basket than rebounds that bounce a longer distance away. While I haven’t done the work to break down these rebounds by individual player, it seems rather likely that the Texas forwards are accounting for a large share of these rebounds on misses at the rim.

The next line in the table looks at the percentage of total rebounding chances that come on missed non-rim two-point attempts. Texas has a higher rate of these chances when compared with the national average. Roughly 40 percent of these chances have come on shots missed by either Jarrett Allen or Shaq Cleare, suggesting that this somewhat higher rate of rebounding opportunities is at least in part due to the fact that so much of the Texas offense focuses on playing through the low post, and many low-post shot attempts end up in this category. According to the next line in the table, the Longhorns are rebounding these misses at slightly below the national average.

Moving down the table, we arrive at the numbers that describe rebounds coming off of three-point shots. The Longhorns get 38 percent of their offensive rebounding chances on missed threes, which equals the national average.

It is on missed three-point chances where the Texas offensive rebounding percentage is at its weakest, compared with the national average. This ranks the Longhorns 267th out of 351 D-I teams in terms of offensive rebounding percentage on missed three-point attempts. With 38 percent of all Texas offensive rebounding chances coming on missed threes, this is the biggest single contributor to Texas’ poor offensive rebounding percentage.

I have also included numbers for rebounding off of missed free-throw attempts, but these results don’t tell us much of importance, as in general a rather low percentage of offensive rebounds come off of free-throw attempts.

The fact that the Longhorns are weakest relative to the national average on getting offensive rebounds when three-point shots miss is consistent with the conclusion that poor rebounding by the Texas perimeter players is the greatest factor in the Longhorns poor output on the offensive glass.

These longer attempts have a far greater chance of rebounding a longer distance from the basket, which is the domain typically occupied by guards. Either the Longhorns aren’t chasing these rebounds as aggressively as is the norm in college basketball or the Texas guards just aren’t getting to these balls.

Rebounding guards

I have my own guess here. Looking over the history of Smart’s teams, his guards usually haven’t come down with many offensive rebounds. There are some exceptions of course, but many of the most prominent ones were “guards” who actually functioned much of the time as Smart’s four-man, such Treveon Graham and Terry Larrier.

Perhaps it is in an effort to focus on getting back on defense, or perhaps it is a consequence of the way his players are positioned on offense, but Smart’s guards generally have not come down with a lot of offensive rebounds.

When we look at some of the best offensive rebounding teams in the Big 12 — West Virginia and Oklahoma State — we see that many of the offensive rebounds pulled down by these teams are recovered by perimeter players. Offensive rebounding is just a greater priority for these teams than it is for Texas, and as a result they pursue more of them and come up with a greater number of them. While it is possible to rebound the offensive glass at a high rate while sending fewer players after those rebounds — here Baylor comes to mind — doing this requires having several highly-effective rebounding forwards to make it work.

While I can’t exactly be sure of this, for Texas there is likely some free offense out there on the floor to be had, simply by sending an extra perimeter player to chase after rebounds. It is up to the coaching staff to make the decision to go after it. In a close game, one or two extra chances can shoot can make the difference.

Wrapping up

If there is one thing to be encouraged about in terms of Texas’ ability to get better on the offensive glass, it is the fine work of Jarrett Allen and Shaq Cleare as of late. Against Oklahoma, both Allen and Cleare each accounted for five offensive rebounds in what was Texas’ best performance on the glass since the start of conference play. Allen and Cleare are both really starting to find themselves and are aggressively pursuing every rebounding chance they can. This is good.

It could be better though. It wouldn’t hurt the offense any if one or more Texas perimeter players could also get in on the action.