A joint training session between the Los Angeles Rams and Cincinnati Bengals was ended early on Thursday after multiple fights broke out.

Rams defensive lineman Aaron Donald reportedly swung Bengals helmets amid one of the skirmishes, with pictures circulating on social media putting the spotlight upon the 31-year-old, leading to calls for a suspension.

In training sessions, clubs, and not the league, are responsible for overseeing the players' conduct in practice and a suspension would therefore be unlikely, though there could be disciplinary action.

The teams elected to end their joint practice session early and Rams coach Sean McVay played down the significance of the fracas later in the day.

"I just see guys swinging and some guys have helmets on, some don't. There's a scrum. You just never know what can occur," he said.

"And my biggest concern is just unnecessary injuries for people that we're counting on, whether it's for our team or the other team."

Bengals coach Zac Taylor made it clear the premature end to the session was not a major loss, with just a few snaps remaining.

"We just called it. We were in the last [practice] period. We got two really good days of work. So was it worth getting the extra couple of plays? No. So we called it," he explained.

The two teams will meet in their final pre-season match on Saturday.