L.A. Rams cornerback Marcus Peters got so pissed off at a heckler in the crowd during Sunday night's game against the Eagles ... he went into the stands and cussed the guy out.
It's crazy ... and TMZ Sports has new footage of the incident showing the moment Rams staff and a player pull Peters out of the stands.
Peters was on the sideline while Philadelphia was beating the Rams, when Peters heard someone in the stands talking trash ... so he talked back.
"Where you from? Where you from, homie?" Peters said as he walked into the stands.
Peters got right in the guy's face and the talk turned even tougher -- "Square ass n**ga. Talk that sh*t now, n**ga. F*ck you mean, n**ga."
At one point, security and even a Rams player went into the stands and pulled Peters back to the bench.
Of course, there have been a TON of pro athletes confronting hecklers lately -- including Leonard Fournette, Montrezl Harrell, Kevin Durant and Patrick Beverley.
Luckily, this time ... the fan shut up pretty quick when Marcus approached him ... smart move.