AUSTIN (AP) — Texas freshman quarterback Sam Ehlinger was held out of practice Sunday and is being evaluated by team doctors for a head injury.

The school announced the move Sunday night. Ehlinger played the entire game Saturday in a 13-10 overtime loss to No. 11 Oklahoma State that ended when he threw an interception in the end zone. Ehlinger had been tackled hard on a run at the start of the possession.

Texas also said sophomore center Zack Shackelford was held out of practice to be evaluated for a head injury.

Texas did not detail the nature of the injuries or how they occurred. Texas did not say when either player might return.

Former Longhorns quarterback David Ash had his career cut short in 2014 after multiple episodes of concussion symptoms.

Ehlinger has passed for 1,419 yards with six touchdowns and four interceptions for Texas (3-4). He is also a physical runner who has rushed for 261 yards as the offense has become more dependent on his legs to move the ball. Texas next plays at Baylor (0-7) on Saturday.

Ehlinger has been physically beaten up in the last two games, both losses.

Late in a loss to Oklahoma two weeks ago, Ehlinger took a hard hit on the sideline and his head hit the ground. He lay motionless for several seconds and stayed out of the game for several plays for evaluation.

After the game, Ehlinger said he was fine and was put through a concussion protocol before he was let back on the field.

Against Oklahoma State, Texas’ first play of overtime was an Ehlinger run to the sideline where he was again slow to get up after a hard hit but stayed in the game.

Ehlinger took over the offense after last season’s starter, Shane Buechele, came out of a season-opening loss with a sore shoulder. Ehlinger started the next two games before Buechele returned in a win at Iowa State.

Ehlinger took over the offense again the next week, rolling up 487 total yards in an overtime win over Kansas State.

Texas also said freshman wide receiver Reggie Hemphill-Mapps was held out of practice because of a knee injury sustained against Oklahoma State.

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