Oxnard, Ventura County --

There was something in the air from the get-go Tuesday, from when well more than half of the 8,326 fans that strolled up to the Dallas Cowboys' practice field were wearing Silver and Black.

"There was a lot of enthusiasm out there," Dallas owner Jerry Jones said, smiling.

After one false alarm - in which Raiders guard Austin Howard got in a couple of uppercuts - there were two all-out brawls at the joint practice of the Raiders and Cowboys. As in, two rosters of players sprinting across the field and diving headfirst into the scrum.

No one was hurt, so both owners could laugh about it afterward.

"That passion, that's what we hoped we would be getting out of putting these teams together," Jones said.

"I am just glad no one took their helmets off," the Raiders' Mark Davis said.

There was supposed to be no tackling to the ground, but some players definitely hit the grass after some hard hits. In the one that set off the first fight, Dallas cornerback Maurice Claiborne - perhaps frustrated at getting beat by Denarius Moore and Brice Butler earlier - put some bad intentions behind his tackle of tight end Mychal Rivera.

Claiborne said Rivera lowered his shoulder first.

"When he did that, I thought it was my cue to go in for the tackle," Claiborne said.

The players, with Oakland's Marcel Reece and Greg Little leading the charge, started jumping on each other with fists flying. It took place right in front of the Raiders' fan section, and one fan swung a souvenir helmet over the fence at Dallas defensive back B.W. Webb.

"With the crowd and just so many bodies ... when you have two teams sharing a field, there are a lot of bodies around," Raiders quarterback Matt Schaub said. "So it definitely ramps up a little bit."

In the second fight, Dallas fullback J.C. Copeland lost his helmet in an exchange with Raiders linebacker Justin Cole.

While Raiders head coach Dennis Allen is not going to endorse fighting on the field, he is not going to criticize it too much either.

"That happens in a competitive environment, but I thought it was good work," Allen said.

Allen was blown away by the turnout and energy level of the Raiders' fans.

"What a hell of an atmosphere to practice football in," he said. "That's what Raider Nation is really all about, man. That was awesome to see those guys come out and support us like that. It almost felt like, at times, that I had to quiet the crowd down just so we could get some plays off."

Dallas quarterback Tony Romo, though, pretty much shrugged at the turnout.

"We're in California. If they didn't have any fans out there, it would probably not be a good sign for them," Romo said. "It's great for the Raiders having that, and it was great for us having the atmosphere. It was pretty unique and something that everybody should get a chance to have in camp."

Briefly: Raiders tight end Nick Kasa got tangled up early in practice and was taken from the field on a cart with an apparent knee injury. ... Magic Johnson and Tommy Lasorda were also in the house, though Johnson, despite being a Raiders fan, said the main reason he came was to meet Cowboys receiver Dez Bryant.