Oklahoma quarterback Dillon Gabriel is concussed after leaving Saturday's 55-24 loss to TCU after taking a hit to the head on a slide in the second quarter.
Gabriel did not return as the Sooners lost their second straight game.
With Oklahoma trailing 34-10, Gabriel ran around the left end,
slid feet first, and was hit by TCU linebacker Jamoi Hodge, who lowered his shoulder into Gabriel's helmet.
Gabriel lay on the turf for several minutes as players from both teams had to be separated.
Hodge was flagged for targeting and ejected.
"I'm not thinking too much about that hit," Oklahoma coach Brent Venables said after the game, adding that he had no further information yet. "It's football it's part of the game.
I'm all about Dillon and his health and his safety."
The Sooners suffered another scary injury in the fourth quarter as defensive back Damond
Harmon lay on the turf after being knocked back on a tackle in the fourth quarter.
Both teams knelt on the field as medical personnel placed Harmon on a stretcher
and carried him away for further evaluation.
"He's had back problems in the past," Venables said.
TCU coach Sonny Dykes said at the start of his postgame news conference that he hopes Harmon is OK.