The two NFC foes played nice during Day 1, but a series of brawls on Tuesday cut the second day of practice short.
"Well, we got through a day and three-quarters," Fisher said. "We had really good work and then unfortunately things got out of hand and we shut it down. It's unfortunate, there's no excuse for it. You can't blame it on anybody, it just happened.
"One thing led to another and it happened. Fortunately no one got hurt."
NFL Media's Steve Wyche was in Oxnard, Calif., for the scrimmage and reported there were three separate incidents. Things got intense when the Rams offense and the Cowboys defense were on the field, which led to the second fight that made its way to a section where Rams fans were standing.
Cowboys teammates Tyler Patmon and Dez Bryant -- who got into their own scuffle earlier this month -- left the melee with dings. Patmon had four red bumps around his forehead and Bryant took a vicious punch to the face. The Pro-Bowl wide receiver, who's been sidelined with a hamstring injury, lost his diamond earring, which was later found by a security guard.
Fights during training camp joint practices aren't new -- Dallas had a tussle with the Raiders last summer and the Texans and Redskinsgot into it recently. The NFL's executive vice president of football operations Troy Vincent sent out a memo last week reminding teams about the prohibition on fighting.
"There's no place for (fighting) in our game," Fisher said. "There's no place for that from a standpoint of being role models in this game and representing this game for kids. That's not how this game goes."
The latest Around The NFL Podcast breaks down Week 1 of the preseason and kicks off a week's worth of spectacular fantasy insight.