Quarterback K.J. Costello, who started seven games for Stanford as a redshirt freshman in 2017, will miss spring practice because of a hip injury, Bruce Feldman of Sports Illustrated reported.
Stanford has not officially commented on Costello's status.
Costello did not begin the 2017 season as the Cardinal's quarterback, but he was their top signal-caller by season's end. He started the final six games for Stanford, including wins over Washington and Notre Dame and close losses to USC in the Pac-12 championship game and TCU in the Alamo Bowl.
This past season, Costello completed 58.8 percent of his passes for 1,573 yards and 14 touchdowns with four interceptions.
Costello passed for 212 passing yards and three touchdowns in the 39-37 loss to TCU in the bowl game. He threw for 192 yards, two touchdowns and no interceptions in the 31-28 loss to USC in the conference title game.
He is projected to be the Cardinal's starting quarterback in 2018.
Quarterback Keller Chryst, who started seven games early in the 2017 season for the Cardinal, announced that he will leave Stanford as a graduate transfer, although he has not named his new school.
While Costello is out of action during the spring, head coach David Shaw figured to get an extended look at backup options Davis Mills and Jack Richardson. However, the San Francisco Chronicle reported Mills, a freshman, won't participate in spring practice because of a setback on a knee injury.
That would leave Richardson, a sophomore walk-on, as the only quarterback available in the spring.