Rosen sustained his second concussion of the season in UCLA's regular-season-closing victory against California. He has practiced every day this week, according to interim coachJedd Fisch, and continues to be monitored by doctors, who have yet to clear him to play.
If Rosen cannot go, Devon Modster would get the start for the Bruins (6-6), Fisch said.
"I don't know,'' Rosen told reporters when asked if doctors have been optimistic about his chances. "I'm not into inferring. But we'll see.''
Fielding questioning from media on Saturday in Phoenix, where the Cactus Bowl will be played, Rosen was asked whether he will play even if he does pass the protocol, given the chance of injury and his future NFL prospects.
Rosen, though, left no doubt with his answers.
"I want to do everything I can to play in this game," he said. "I love these guys. I would give anything to get another game after this."
The quarterback said his position minimizes the risk of injury compared to a position such as running back. Current NFL rookies Leonard Fournette and Christian McCaffrey skipped bowl games last season due to the risk of injury and ended up being taken in the first eight picks of the 2017 NFL draft.
"For them, it is not an issue of if they are getting hurt. It's an issue of how severe," Rosen told reporters. "Most of those guys get banged up to some extent every single game. Quarterback is unique. We will take a few licks here and there, but nothing like the beatings those guys take.
"People also have to realize that a lot of these guys have family, kids. A lot of guys have to support families. They may want to play in a bowl game. But maybe they're locked into their futures and they need to take care of a kid, or family, or brother or sister. People should look into each of their stories and see how football is affecting their lives. I'm fortunate. I'm a quarterback. Every situation is unique.''
As for his NFL draft status, Rosen, a junior, said he has yet to make a decision. He noted that he'll go home after the Cactus Bowl, discuss with his parents and go from there.
ESPN analysts Mel Kiper and Todd McShay have Rosen as the top-rated draft-eligible quarterbacks. Kiper has Rosen going fourth overall in his latest Big Board. McShay has him going No. 1 overall in his latest Top 32.
McShay on Rosen: 'Most gifted pocket-passer in draft class'
UCLA QB Josh Rosen's draft stock is at an all-time high but could have one final test, if cleared, in the Cactus Bowl, Tuesday, December 26th at 9 p.m. ET on ESPN.