Another instant classic from Katie Taylor and Amanda Serrano was marred by headbutts, a nasty cut and a controversial decsion.

Amanda Serrano has backtracked on her claims that Katie Taylor intentionally tried to headbutt her during their epic fight on Friday night.

Taylor retained her unanimous super lightweight championship in a razor-thin unanimous decision over Serrano in a slugfest remarkably similar to their epic bout in New York two years ago.