MOBILE, Ala. (AP) South Alabama quarterback Cole Garvin injured his right ankle on the opening series against No. 11 Oklahoma State.
The school announced later that Garvin wouldn't return to the game.
Dallas Davis replaced him on South Alabama's second series. Davis started 10 games last season then missed spring practice while recovering from shoulder surgery.
He led the Sun Belt Conference in total offense last season and was second in passing yards per game. Garvin won the starting job in preseason camp.
Garvin went to the medical tent after the first series Friday night, when he was sacked on first down and was forced to run the ball on third.
Shortly after, he was taken toward the Jaguars' locker room on a cart before returning to the sidelines.
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