Katie Taylor survived a brutal onslaught in the fifth round that saw her busted open to win on a split decision in Madison Square Garden.
The Irish woman won on points against Amanda Serrano in a fight of the year contender in the early hours of Sunday morning.
Fight highlights below show Taylor surviving an incredible flurry of punches from her opponent that saw her wobbled like never seen before.
Fight highlights
Fight report
From the bell, Serrano was as aggressive as promised. Taylor manoeuvred the ring well, avoiding major shots from the challenger, who is one of the most feared punchers in the women's game.
In the second round, the Puerto Rican continued her onslaught, having a bit more success than the first, where Taylor was able to counter with the left hook on a number of occasions. Both women had upped the ante by the third and had to be separated after Serrano was pushed into the ropes.
The rounds were tight early, with Serrano perhaps edging the early exchanges with her late attacks in the round. Serrano's controversial and outspoken brother-in-law and co-manager Jordan Moldanado did his best to taunt the Irish fans, but focus couldn't be drawn from the tow multiple-time world champions.
Serrano had called for 12 rounds of three minutes before the event, and as things began to heat up one was left wondering if perhaps they were necessary. Taylor's slip right-hand counter caught Serrano in the middle of the fourth.
Understanding she may be down on the scorecards by the fifth, Serrano began to push the pace further, unloading on Katie in the corner, and ultimately wobbling her in a dominant round heading into halfway.
The Irish woman was badly hurt coming into the sixth, and Serrano took full advantage, punishing the champion with damaging combinations. Never down as a professional, Taylor managed to survive the gruesome onslaught, which saw Serrano bloody her nose and throw well over 120 punches in just six rounds.
Taylor appeared to have regained her footing by the seventh, and wasn't subject to the same volume of abuse she had suffered in the previous four minutes. And by round eight, she was back into her stride, connecting a lot more with Serrano as the seven-weight world champion began to slow.
There had been concerns about the challenger's ability to bulk up to Taylor's weight in a sustainable way, and she appeared to be struggle as they headed into the championship rounds. Ever the aggressor, Serrano became much more susceptible to Taylor's counter-punches, and the pair both headed into the tenth knowing they weren't out of the woods.
With seconds to go in the tenth, it was anyone's fight as Serrano sported a bloodied eye to match Taylor's nose. They went hell for leather in the closing seconds, but neither was able to score the all-important fight clinching knockdown. Two of the judges gave Taylor the nod by scores of 97-93 and 96-93 to ensure the belts will be flown back to Ireland. Serrano was awarded the fight 96-94 by the third judge.
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