Prince, who was named the starter but was slated to split time with Richard Brehaut, kept the ball on a 4-yard run early in the second quarter, but he was upended by Houston cornerback D.J. Hayden near the UCLA sideline and crashed down hard on his head and shoulder area.
"I blacked out there for a couple of seconds," Prince said. "It's diagnosed as a mild concussion. I'll have some tests I'll have to deal with, but I feel OK now."
Prince had completed 3 of 3 passes for 58 yards and had 8 yards rushing at the time of the injury. UCLA trailed 10-7 at the time. Brehaut replaced Prince, but on his fourth play, he and Jordon James botched a handoff exchange and UCLA lost the ball. Houston scored six plays later for a 17-7 lead.
Brehaut settled, however, and led a second-half surge. The Bruins trailed 31-14 at halftime but closed to within 31-28 at the end of the third quarter. Brehaut finished with 264 yards and two touchdowns passing and 87 yards and a touchdown rushing.
Prince said he was trying to get out of bounds on the play that knocked him out of the game, but that the Houston defender got to him before he could get to the sideline.
"I flipped and the next thing I knew I was on the bench," Prince said.
It's not the first time Prince has been knocked out of a game. He suffered a broken jaw against Tennessee two years ago and missed two games. When he returned, he was knocked out of the game against Washington with a concussion but returned the following week.
Last season, Prince missed much of training camp with a strained oblique but did not miss a game. He sat out against Washington State after a knee injury the week before against Texas and ended up having season-ending microfracture surgery on that knee a few weeks later.
"It's very frustrating for sure, especially going through camp and all the work I put in to just play one quarter and be done with it that quick," Prince said. "It's just a mild thing, and I'll be back hopefully as soon as next week. They're very cautious about concussions here so it'll be a day-by-day thing and we'll see how it goes."
Peter Yoon covers UCLA for ESPNLosAngeles.com.