LOS ANGELES - If yesterday's practices by Rose Bowl opponents Penn State and Southern Cal were filmed for a movie, an editor likely would have cross-cut scenes between the camps to illustrate the differences.

Scene 1, USC - Trojans players and coaches walk through a mass of high-fiving fans and onto their practice field.

Scene 2, Penn State - Nittany Lions players and coaches walk behind their Kremlin Wall and onto their practice field.

Scene 3, USC - Trojans fans talk with players as they warm up and then line the field as practice begins. The atmosphere is circus-like.

Scene 4, Penn State - The Nittany Lions stretch for 15 minutes. A handful of media types is on hand to watch or photograph this exercise. A pin drops. Everyone hears it.

Scene 5, USC - Trojans coach Pete Carroll tosses a football back and forth with a wide receiver. He then sprints to the next drill along with his players.

Scene 6, Penn State - Lions coach Joe Paterno sits in a golf cart, with driver and a cane nearby.

For years, Paterno has kept both the media and Lions fans away from practices. Some have had a problem with this. Others have not. Carroll, when he went to USC eight years ago, maintained predecessor Paul Hackett's policy of keeping practices open to the public. But he added the element of chaos to the ritual, and it's become a signature of the program under his tenure.

"We want practice really hard every day, and the more atmosphere the better," Carroll said yesterday. "We never play without crowds. . . . The more energy around the practice field the better, whether we can generate it or we can draw it from the crowd."

Carroll wants distractions, and there are many. Fans of all ages, sizes and backgrounds can wander through a gate and onto the sidelines. And they're everywhere. Some are in the end zones. Some are perched above on overlooks. Many are camped out in portable chairs that hug the field.

"It works great," said Jerry Conn, a Class of 1964 wide receiver who played for John McKay. "It's kind of a two-way street. They sometimes run over into us. You have to be careful. Sitting in these chairs is not the best idea."

Much of the enthusiasm comes from USC's success since Carroll came aboard. The Trojans are 87-15 in that span. But a lot of the excitement has been generated by the eternally youthful Carroll, who wore a red hoodie yesterday and signed autographs for 15 minutes after practice.

The players love it, too.

"Everybody here is a Trojan, whether they went here or they know somebody that went here or their kids are here now," quarterback Mark Sanchez said. "It's all a part of this atmosphere, and that's what Trojan football is all about. We're just a giant family and they're like our extended family on the sidelines."

Penn State, meanwhile, will go about its practices this week in relative anonymity. And that's the way Paterno, who did not meet with reporters yesterday, likes it. To the 82-year-old coach, too much access is too much distraction.

There is an element of secrecy to the closed practices, though. Coaches are always suspicious of spies giving plays or reports on personnel to enemy camps. As open as USC practice was, there were a few people who were barred from most of the practice: the Penn State beat reporters.

Carroll, though, said it wasn't because of paranoia.

"I'm not worried about you figuring out what we're doing," he said, "because I can't tell half the time, either."

Contact staff writer Jeff McLane at 215-854-4745

or jmclane@phillynews.com.