The Longhorns will walk on thin ice Saturday when they head to Ames, Iowa, for a must-win game against the Iowa State Cyclones. Last weekend, Texas slipped past Kansas State in a home game that kept its Big 12 Championship hopes alive. Later that day, another thrilling Big 12 matchup occurred when the Cyclones nearly edged out then-No. 9 Oklahoma in their 42-41 loss. Excellent quarterback play and defensive performances from Iowa State nearly brought down the Sooners at home, so what should the Longhorns expect this weekend as they hit the road?

Here are four Iowa State players to watch this weekend against Texas:

No. 15 Brock Purdy — Quarterback

Sophomore quarterback Brock Purdy has been a force of nature this season. Purdy rose to the occasion in Norman, Oklahoma, last weekend, throwing five touchdowns and rushing for a score too. When Texas met Iowa State last November in Austin, the Gilbert, Arizona, native rushed for -11 yards, threw an interception and completed just 10 of 23 passes. But this game may be different.  Purdy’s 20 passing touchdowns and seven rushing scores through nine games display his improvement. All of these factors, coupled with Iowa State’s home-field advantage and Ames’ near-freezing temperatures, should be concerning for a Texas defense that gave up two touchdowns to Kansas State in the first quarter of last week’s matchup.

No. 34 O’Rien Vance — Linebacker

Last weekend marked Texas junior quarterback Sam Ehlinger’s fifth consecutive game of sack trouble, as members of Kansas State’s defensive line brought him to the ground twice. If the Longhorn offensive line doesn’t prepare for redshirt sophomore O’Rien Vance, it could be another rough outing for Ehlinger. Vance is one of the Big 12’s top linebackers. The Cedar Rapids, Iowa, native has recorded a team-high 6.5 sacks this season to go with one forced fumble. If Purdy plays anything like he did at Oklahoma, the Texas offense will have to light up the scoreboard. Ehlinger can’t score touchdowns laying on the ground, so the Longhorn offensive line must do what it takes to limit Vance.

No. 88 Charlie Kolar — Tight end 

When Iowa State trailed Oklahoma 42-35 last weekend, redshirt sophomore Charlie Kolar scored the touchdown against his hometown team that would bring the Cyclones within one point of the Sooners. The next play, quarterback Purdy threw an interception on Iowa State’s two-point conversion attempt that would’ve given the Cyclones the lead. Kolar, who was momentarily open during the play, raised questions about what could have been had Purdy found him. The Norman, Oklahoma, native knows how to make plays and find the end zone, and the tight end’s team-leading six touchdowns are a testament to his impact. Kolar’s average 14.3 yards per reception and 6-foot-6 frame might be hard for a young and recovering Texas defense to stop.

No. 55 Zach Petersen — Defensive End

Defensive end Zach Petersen impressed at Oklahoma last week, recording a forced fumble and a sack. Last season, Petersen totaled one solo tackle; this year he has 19. The much-improved sophomore from Long Grove, Iowa, has also increased in size, weighing in at 262 pounds compared to last year’s 236 pounds. With defensive starters falling to injury, this season has seen Petersen step up for Iowa State. Strong showings against Big 12 opponents TCU and Oklahoma cemented Petersen as a key piece of the Cyclone defense — one that could get in the way of Texas’ plans Saturday.