He could wind up in Denver, or Buffalo, or East Rutherford, N.J., but former UCLA quarterback Josh Rosen was unmistakably Southern Californian as he shuffled around under cloudless skies in flip-flops and a baggy hoodie.
"I live and die in these things," he said, motioning to his feet.
But Rosen did his best work Thursday in cleats, cutting through a light breeze with a wide array of passes, deftly rolling out and hitting his receivers in stride, and, moments after finishing his on-campus workout, hoisting his mom off her feet with a bear hug.
"I'm his biggest fan, and he's still my little kid," Liz Rosen said of her 6-foot-4 son. "I just love seeing his happy 10-year-old self. Through all the seriousness, it comes through."
Rosen actually turned 21 last month, and is expected to go in the first round of next month's NFL draft, perhaps in the top 10. He's widely considered the best pure thrower in a strong class of quarterbacks, and was the main attraction of a pro day that attracted about 100 league coaches, executives and scouts.
Denver, which just signed Case Keenum but might still use the No. 5 pick on a quarterback, showed up in force, the contingent including GM John Elway, coach Vance Joseph and personnel advisor Gary Kubiak.
Yes, there were other UCLA prospects to study, including tackle Kolton Miller (a potential first-round pick), center Scott Quessenberry and receiver Jordan Lasley, but there's no question the main spotlight was trained on Rosen, who originally planned to throw 55 passes but trimmed seven or eight because of various injuries to his receivers.
The wind was strong enough to spin a weather vane, but Rosen was unflappable. His throws were largely on target.
"If you throw a tight spiral, it doesn't matter," he said. "But ball's ball. I'm not going to change the pro day and say, 'Hey, can we hang out for the wind a little bit?' But it was fun. Threw it pretty well."
Everyone knows Rosen can sling the ball. Teams mulling whether to invest millions of dollars in him want to know his personality, how he interacts with teammates, how he handles both success and setbacks.
"I think they wanted to see what kind of teammate he was, and I think he did a great job," said Quessenberry, who snapped the ball to him in college. "He was very encouraging on the bench press. He was the last guy in the gym watching vertical [jumps], me and him right there together. People are looking for that, what kind of teammate he is. I think he went out there today and showed that he's an A-class guy, A-class teammate, A-class person."
Rosen, who only threw Thursday and didn't participate in any other drills, has no problem with teams pulling out the magnifying glass to examine his personality.
"I would love to get picked in the first round, and in that round you're investing quite a bit of money," he said. "Whether it's an issue or not, you want to know every single thing you can about a person. If you're going to invest in stocks you're going to do all your research before you sink some good money into said company, so you're going to do the same with your players."
"I thought he threw on the run a lot more than I was expecting him to," said former NFL quarterback Matt Hasselbeck, an ESPN analyst. "He was moving in the pocket a lot more. He was very accurate on the run to the left, that was something that stuck out to me. It was almost like he made a concerted effort to be moving in the pocket. 'Hey, I believe in my mechanics, I believe in my base. I'm not going to just drop back straight and throw the ball.'"
Clearly, Rosen has some lateral mobility. Now, he's hoping for upward.