OXNARD – The "Black Hole," the nickname given to the Oakland Raiders' crazed fan base, arrived in Oxnard on Tuesday to support their team during the first of two practice sessions between the Raiders and the Dallas Cowboys.

Tuesday's workout marked a homecoming of sorts for the Silver and Black. From 1985 through 2005, Oakland used the River Ridge facility as its training camp home.

But unlike back then, when Raiders owner Al Davis used to put black tape on the fences around the field to prevent anyone from watching, fans of both teams engulfed both sides of the practice facility, watching their respective team battle on the field for roughly two hours.

The attendance at the River Ridge fields was 8,326.

A long line of cars filled with both Cowboys and Raiders fans stretched down Ventura Road more than two hours before the parking lot was scheduled to open at noon.

The stands on both sides of the field were filled close to two hours before the start of practice. The two fan bases were kept separated as much as possible, with Raiders fans lining up on the field closest to River Ridge Golf Course. Cowboys fans got the "home" stands closest to the parking lot and concession stands.

At about 3:30, the buses carrying the Raiders players pulled into the parking area, drawing wild cheers from the Oakland fans. Looking like a high school football team showing up to an away game, the Raiders players walked off the bus in full gear, carrying their helmets and shoulder pads.

As they hit the field, chants of "Welcome Back," and "Bring Them Back," showered down from the Raiders Nation.

As the teams warmed up, the two fan bases took turns berating the other team. It was perfect foreshadowing for a practice that featured plenty of hitting, most of it before, but some after the whistle.

For the first hour, the two teams worked on separate fields, but finally the fans got what they were looking for. The Raiders offense squared off against the Cowboys defense on the field in front of the Raiders fans.

Cowboys fans were treated to their offense taking on the Raiders defense.

The two teams were relatively behaved for the first half of the team sessions.

For much of their session, the Raiders offense had good success moving the ball against the Cowboys defense.

Oakland quarterbacks Matt Schaub and Derek Carr both looked sharp in both 11-on-11 drills and later in the seven-on-seven competition. Raiders running back Latavius Murray broke off several nice runs.

Cowboys rookie cornerback Terrance Mitchell celebrated after making several nice plays, later bringing taunts from the Raiders fans every time a player caught a ball in front of him. Mitchell, who has drawn praise from Cowboys head coach Jason Garrett, played right along, adding to the atmosphere.

During a competition between the Cowboys defense linemen and Raiders offensive linemen, Dallas defensive tackle Davon Coleman and Oakland offensive tackle Austin Howard exchanged a few blows after a heated competition.

Not long after that, during the second 11-on-11 session, Cowboys cornerback Mo Claiborne picked up and slammed down Oakland tight end Mychal Rivera near the sideline next to the Raiders fans.

Rivera took exception to the hit and went after Claiborne. Within seconds, players from both teams were pushing and shoving. The scrum eventually pushed up against the fence where fans were standing, leading one Raiders fan to get involved by swinging a souvenir helmet that slammed into the helmet of Dallas cornerback B.W. Webb.

Webb took a swing at the fan.

"I thought it was another player, but then I realized it was a fan," Webb said after practice. "I said, ‘Did you just hit me with a helmet?' Just a crazy Raider fan I guess. You always get in little brawls on the field, but nothing usually breaks out into the fans.

"Thank God I still had my helmet on. We tried to keep things down, but once you get out here, the emotions get going and you start flying around and it happens. It's football."

A few minutes later, a smaller fight broke out between the Cowboys offense and Raiders defense, bringing a quick end to the session.

After the practice ended, Raiders fans ran in unison to the Oakland players, who signed autographs.

Raiders fullback Marcel Reese gave props to the team's fans.

"It was basically training camp for another team's fans and they (the Raiders fans) outshowed them," Reese said. "The Cowboys have been here for years and years and they are going to be here for years more, but we come down here one time and we outshow them.

"The Raider Nation is about loyalty. It was exhilarating. We expected a gamelike atmosphere and it was. Everyone was out here to get after it and compete."

When asked if he was surprised by the large crowd out to support the Raiders, Cowboys quarterback Tony Romo said no.

"It's California. If they did not have fans out here, it would be strange," Romo said. "It made the atmosphere unique."