Amanda Serrano said Katie Taylor "100 percent" intentionally headbutted her during Friday night's undisputed women's super lightweight title bout.

Taylor retained her belt with a unanimous decision on Friday as she earned a 95-94 score on all three judges' scorecards.

"I think 100 percent, because she does it in every fight," Serrano said on Friday night when asked if Taylor's headbutt was intentional. "It's not the first fight. It was my first fight out of 40 something fights, my first cut, ever, was with Katie Taylor. Like I said, she did it with Chantelle Cameron and it's been in other fights. I've seen her use her head dirty."

Serrano suffered a significant above her eye after a headbutt during Round 4. She shared an image of the wound after the win.

"I'm a ruthless warrior & Katie is my buddy but Damn her best attribute is her head," Serrano wrote.

Serrano said in her post-fight interview that the cut had impacted her performance during the fight.

"Every time you get a cut, it bothers. You get blood in your eye, it hurts, she kept headbutting me," Serrano said. "But we knew that from the very beginning, from the first fight. That's what they do. It's not only my fight."

Referee Jon Schorle addressed the headbutts during the fight, deducting a point from Taylor for hitting Serrano's cut in the eighth round.

When announced, the controversial decision received heavy boos from the crowd at AT&T Stadium in Arlington, Texas.

The bout between Taylor (26-1, 6 KOs) and Serrano (47-3-1, 31 KOs) took place on the undercard of the title fight between Mike Tyson and Jake Paul. Taylor also won the pair's previous fight, which was a split decision in April 2022 at Madison Square Garden in New York.