Jimmy Butler's Shorts Stained During Mavericks Game, Fans Suspect Poo

All eyes were on Jimmy Butler's butt Wednesday night ... 'cause his shorts had a dark yellow stain on 'em -- leading many to believe he had crapped himself mid-game.

The unfortunate scene for the new Warriors star played out as he and Golden State were fighting to pull off a win vs. the Mavericks at the American Airlines Center in Dallas.

Eagle-eyed viewers of the tilt noticed that as Butler was making a drive to the lane with the Dubs down 109-107 late in the fourth quarter ... some unusual coloring had appeared on his white shorts.

When his tush was magnified by X users, it certainly seemed like Butler had had a bit of a bathroom accident.

Jimmy -- who was just traded to NorCal from the Heat earlier this month -- didn't seem too bothered by the situation if it was what everyone thought it was, he finished with 21 points, nine rebounds and seven assists.

Golden State ended up losing the matchup, though -- so, seems it was a crappy night for the forward either way.