Ricky Hatton dredged up a performance full of guts and grit to claim the WBA welterweight title from Luis Collazo in Boston then admitted: "That was the toughest fight of my life."
Hatton earned a 115-112 (twice) 114-113 verdict over awkward New Yorker Collazo, who almost had the Manchester 'Hit Man' out on his feet in the final round of a gruelling contest.
Even the great Kostya Tszyu had failed to put Hatton in as much trouble as Collazo, a 25-year-old who was well regarded for his slippery southpaw skills but boasted little reputation for power.
Such a major test was the last thing on Hatton's mind when he floored the champion with a left hand in the opening 20 seconds of the fight - but from that moment Collazo's clean counter-punching caused no end of problems.
And afterwards Hatton, badly bruised around both eyes, conceded his ambitious move up to the 147lbs weight limit for the first time had proved more difficult than he had initially envisaged.
Hatton said: "I still believe I am a light-welterweight but moving up a division I did notice the difference and Luis hurt me several times in the fight.
"I am obviously giving guys a better chance because they are bigger than me. But the way I was hit and hurt in the last round and my response to it showed I can cope."
Collazo predictably called for a rematch but tellingly added he believed Hatton would put his 41-fight unbeaten professional record in grave danger by continuing to pursue titles at 147lbs.
"He has got to move back down because I am not a puncher and I had him hurt. That shows you how much he needs to stay at 140lbs - but if he wants he can prove it in a rematch," said Collazo.