Mikala Compton/American-Statesman / USA TODAY NETWORK

The Texas Longhorns will be without defensive back Derek Williams for the first half of the College Football Playoff semifinal after his appeal for a targeting ejection was denied, according to multiple reports Tuesday.

Williams was appealing a targeting call that opened the second half of the Longhorns' Big 12 Championship win on Saturday. A blocker on Texas' kick return, Williams appeared to make helmet-to-helmet contact with an Oklahoma State player. The call was upheld after review, and Williams was ejected from the game.

Though only a freshman and technically not a starter, Williams has taken on a key role in Texas' defensive back rotation. He notched 39 total tackles, one for a loss, and two pass breakups in 11 games during the regular season. His 373 snaps played at safety this season is third-most among the team's defensive backs.

The news comes as No. 3 Texas (12-1, 9-1) is dealing with senior safety Jalen Catalon's announcement Monday that he intends to enter the transfer portal as a graduate transfer.

Williams has rotated play mainly with Jerrin Thompson, Michael Taaffe and to a lesser degree Kitan Crawford.

Crawford is expected to see expanded action while Williams is out during the first half of the Sugar Bowl against Washington on Jan. 1.

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