Amanda Serrano Shares Gruesome Injury Pic After Loss to Katie Taylor

Boxer Amanda Serrano posted a wicked picture of the huge gash over her eye ... right after being defeated by Katie Taylor in a classic bout Friday night at the Mike Tyson vs. Jake Paul event.

Along with the hard-to-look snap ... she wrote, "To my fans I’m going to always give it everything I have. I’m a ruthless warrior & Katie is my buddy but Damn her best attribute is her head. No punching power but hard ass head lol."

Amanda got the nasty wound during her loss to Katie in a unanimous 95-94 score ... a somewhat controversial victory due to the massive cut after an accidental headbutt in the sixth round.

Katie's jabs kept reopening the cut ... and obviously making the gash bigger as each round progressed.

Amanda seemed pretty shocked by her loss last night too -- tweeting, "I landed 107 more punches, she got a point deducted and I lost 95-94 lmfao."

Katie's win was met with cheers ... but also a lot of boos. Still, the popular consensus on X was the match was the most entertaining of the night after the lackluster Tyson-Paul bout.