Texas Tech football is officially on the College Football Playoff bubble, and the Red Raiders can't afford another stumble.

After debuting at No. 15 in Tuesday night's first CFP rankings, Joey McGuire's team faces a critical Big 12 showdown against West Virginia on Saturday at Galaxy Stadium in Lubbock.

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The Red Raiders enter at 7-1 overall and 4-1 in conference play, but their 37-24 loss to Cincinnati two weeks ago has left little room for error.

With four regular-season games remaining, Texas Tech needs to win out and put itself in position to compete for another Big 12 championship.

Saturday's matchup against the 5-3 Mountaineers presents a challenging test, especially with injury concerns affecting both programs.

Texas Tech remains without wide receiver Donte Lee Jr., who suffered a season-ending knee injury. Running back Cameron Dickey has also been sidelined with an ankle injury, while receiver Jalen Jones has appeared on injury listings because of an undisclosed issue.

West Virginia has encountered its own injury problems, particularly in the backfield.

Running backs Andre Devine and Mason Boswell have been listed out with undisclosed injuries, while Caleb Talley and Lennox Autry have carried questionable designations on earlier reports. Tight end Caden Ball has also been sidelined.

Neither team's updated official game-week availability report had been released as of Tuesday, leaving several statuses unresolved.

For Texas Tech, the biggest storyline might be quarterback Thomas Castellanos.

After replacing Will Hammond against Arizona, Castellanos provided the offensive spark McGuire desperately needed.

The veteran completed 11 of 24 passes for 144 yards and two touchdowns while rushing for 117 yards and another score in the Red Raiders' 34-26 victory.

"He gave us juice today," McGuire said following the win.

Castellanos is listed as the starting quarterback again this week, giving Texas Tech a dangerous rushing combination alongside J'Koby Williams, who erupted for 175 yards against Arizona.

That ground attack could be decisive against a West Virginia defense allowing 166 rushing yards per game.

But the Mountaineers have their own offensive weapon.

West Virginia averages 261.6 rushing yards per game, ranking among the nation's best. Texas Tech counters with a defense surrendering just 94.9 yards on the ground.

Something will have to give.

The Red Raiders also have an opportunity to establish a school-record 14-game home winning streak after matching the previous mark against Arizona.

Still, Saturday is about much more than protecting home turf.

At No. 15, Texas Tech currently sits outside the projected 12-team playoff bracket. Winning its final four regular-season games, beginning with West Virginia, would strengthen its resume and keep its conference championship hopes alive.

But another loss could effectively eliminate the Red Raiders from realistic at-large consideration.

After West Virginia, Texas Tech still faces Oklahoma State, Baylor and TCU.

The path is clear, even if it won't be easy.

Win out, contend for the Big 12 title and force the playoff committee to reconsider.

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Anything less could leave the Red Raiders watching the postseason from home.

Kickoff is Saturday at 8:30 p.m. CT on ESPN.

Source: Yahoo Sports