Already without starter Manny Wilkins for Saturday night's game against UCLA, Arizona State had to turn to its third-string quarterback after backup Brady White was knocked out of the game late in the fourth quarter with a right leg injury.
Making his first career start, White had some shaky moments, but led the Sun Devils on four scoring drives in the second half of their 23-20 win in Tempe, Arizona.
He finished with 179 yards passing, one touchdown and an interception, but couldn't put any weight on his leg after being sacked by UCLA's Kenny Young.
White later went to the locker room on crutches and was replaced by Dillon Sterling-Cole, who went 0-for-1 and threw an interception in the end zone.
"Hopefully, we'll get good news on Brady, but it doesn't look good," Arizona State coach Todd Graham said.
The Associated Press contributed to this report.