Sandy Ryan was hit with a can of red paint en route to Madison Square Gardens, before losing her WBO welterweight world title to Mikaela Mayer.
Despite being advised by her trainer to pull out of the bout, Ryan proceeded to the venue and took the ring as scheduled.
The Briton lost a tight match on a majority decision, leaving Mayer as the world champion.
Tensions had been high prior to the fight, with Mayer accusing Ryan of poaching her long-standing coaching team, which Ryan denied.
After the fight, Ryan said: “Before coming to the venue, I had a hit and run [with paint outside the hotel]. And that was definitely set up. I’m not taking nothing away from the win, but it unsettled me.”
Sandy Ryan was hit with paint
“Walking to the venue, I was shook up. And then it threw me off a bit of my game plan because I just wanted to fight. And you saw at the start of the fight, I was handling her quite well on the jab. I was boxing her and then I started to pick it up. But then, I was obviously pushing it too hard.”
Please use Chrome browser for a more accessible video player
Mayer reacts to her WBO welterweight title victory over Ryan who believes the pre-fight paint-throwing incident ‘unsettled her’
Mayer had the upper hand in tense exchanges in the ring, clinching the victory with scores of 97-93 and 96-94, overruling one judge’s 95-95 draw.
After the match, Mayer told Sky Sports News: “I was just as surprised as everyone else. I was still upstairs, waiting for the call that my car was there.
Please use Chrome browser for a more accessible video player
Mayer denied being involved in the incident that saw paint thrown at Ryan ahead of their clash
“I heard that paint had been thrown on Sandy. I had no idea. I was shocked. I thought it was horrible. I would never go that far.
“Then I heard that she thought it had something to do with me and my team, which is disappointing. Obviously Sandy is my rival and my opponent but I would never go that far.”