Scary moment on the NHL ice on Wednesday ... Nathan MacKinnon -- one of the league's best players -- gushed blood everywhere following a violent hit, and had to leave his game early.
The gnarly scene all went down just minutes into the Avalanche's tilt with the Bruins in Denver ... when MacKinnon was trucked by Boston winger Taylor Hall as he tried to get after a puck.
Video shows Hall's shoulder went right into MacKinnon's face, and, unfortunately for the Avs star, his own stick caught him in the nose during the play as well.
The 26-year-old lay on the ice for several minutes ... bleeding all over the place, before he was eventually helped off by trainers into the locker room.
MacKinnon never returned to the game, and it's unclear the extent of his injuries. The Avs only said that he had an "upper-body" ailment.
Seems pretty clear from the images, though, that the guy might need to get his face fixed soon.
As for the game, somehow, without their best player for most of the night, Colorado rallied to beat Boston, 4-3, in an overtime thriller.