The official line is there is quarterback competition in Westwood. The naked eye sees Rosen. Although coaches say they are not sure whether he is ready, after four weeks of spring practice the indications are he is more than capable.
His time with reporters showed he has the personality and poise to handle the job.
On the battle with Jerry Neuheisel, Asiantii Woulard and Mike Fafaul, Rosen said, "Outside of the competition on the field, you wouldn't believe there was any sort of competition. Mike, Jerry and Asiantii have been helping me a ton. They are not going to give me a snarl when I ask a question or hope I mess up on the field."
On how he has assimilated into the program, he said, "I'm kind of that pesky little freshman who comes in and thinks he's the king of the world. But they have welcomed me with open arms."
On whether he wins the job, he said, "I'm not going to walk in here and say, 'I'm the starter.' I got to come out here and try to complete every pass, make the right read every time, put on as much weight to get into physical shape, get as good of grades as I possibly can and present myself in a positive way to everyone."
If Rosen handles himself as well on the field as he did with the reporters, the Bruins could be all right. Even when talking to the media, Rosen showed an ability to correct mistakes.
"I have not been an anchor in meetings, where the coach has to pull me aside and slow everything down for me," Rosen said. "It helps everything go a little more smoother."
He quickly added, "smoothly."
Rosen came to Westwood under a microscope. He was considered the top high school quarterback in the nation at Bellflower St. John Bosco last fall. He enrolled early to participate in spring practice and has been scrutinized from the first workout.
But the biggest adjustments have been outside the football program. On the field, Rosen has gone through some growing pains but has handled everything thrown at him.
His three pass attempts in 11-on-11 drills Thursday were telling.
Rosen lofted a nicely thrown deep ball only to have defensive back Ishmael Adams break up the play with a quality effort. The next play was a bad snap, but Rosen managed to complete the pass. That was followed by a breakdown on the offensive line, resulting in a sack.
None of it fazed Rosen. He wound up completing 11 of 17 passes, including seven of the last 10.
"The biggest thing is the speed," Rosen said when asked about the difference from high school. Even at that, Rosen said his time at St. John Bosco High prepared him for it.
As a high school junior, he played with receiver Shay Fields (Colorado), defensive back Jaleel Wadood (UCLA) and offensive linemen Damien Mama (USC). All made significant contributions to their college teams as freshmen last fall.
In fact, in some ways, this is easier than high school.
"I was expecting to be yelled at a lot more," Rosen said. "At Bosco practices, I got used to be yelled at about everything I did, even if it was the right thing."
The big changes have been off the field. Rosen said he was five minutes late to each of his classes the first week.
"I underestimated how long the walk was," Rosen said. "You got to find your way to classes and find times to eat."
Getting plenty to eat is key for Rosen, who weighed 211 pounds last week but hopes to reach 220 by the first game. It's more challenging than it sounds.
"I'm trying to put in four or five meals a day," Rosen said. "Finding chunks of windows to eat is tough."
The one question concerning UCLA fans the most went unanswered.
Asked if he will be the starting quarterback, Rosen said, "We'll see. Whatever quarterback wins will deserve the job because we're all battling our butts off."