It's no secret at this point in the season that Texas Tech struggles in rush defense -- former TCU secondary coach Chad Glasgow's 4-2-5 scheme ranks 114th in the country, giving up more than 225 yards per game and close to five yards per carry.
The porous front seven gave up nearly seven yards per carry to Nevada when the Wolfpack gained 312 yards and were gashed by Iowa State last week in the loss for 368 yards at a rate of 5.58 yards per pop.
Given all of that and the emerging Longhorn identity as a physical running team, the gameplan on Saturday morning will almost surely revolve around running early and often to take advantage of the strength of the Texas offense and the weakness of the Texas Tech weakness.
However, given injuries to the Red Raider secondary, the Longhorns may have some more opportunities in the passing game that otherwise might not be available.
One of the top performers in that Tech secondary, sophomore safety Terrence Bullitt, who is fourth on the team in tackles and second in tackles for loss, separated his shoulder against Iowa State and will miss the Texas game.
In Bullitt's place will be senior Jared Flanel, a special teams player for Tech for most of his career who will be making his first career start.
Additionally, a recently converted wide receiver who has been playing the position for a matter of days, Shawn Corker, could be a starter at cornerback, not a great sign for the overall strength of a unit that has been suffering with injuries of its own and may simply be waiting to be exposed.
With Glasgow's defense committing resources to stopping the running game, Harsin may take more chances downfield than he did against Kansas, when he was mostly content to run the ball.
The issue is that Jaxon Shipley hasn't been practicing this week and could miss the game. At best, he'll be hobbled and not at full speed.
Add to it the fact that Ash has struggled connecting with the only sort-of proven deep threat on the team in Mike Davis, even in practice, and the Longhorns may not have the ability to exploit the possible weakness against a secondary that has only had one poor game this season, against the pass-happy Sooners.
Harsin's major commitment as a coordinator is to the running game and the natural outgrowth of success there is the play-action passing attack off of it, so Harsin isn't going to be discouraged by failures in games or practice if the opportunities are there -- he will take them in a close game if necessary, even with an offense that can't afford to get into long down-and distance situations.
If the Red Raiders do decide to outnumber the box and can stop or slow the Texas running game, will Harsin be able to respond? It will be a key to the game.