Ricky Burns bounced back from a first-round knockdown to blemish the once-perfect record of Roman Martinez in their WBO super-featherweight title fight.
The Scot was knocked to the canvas early and was on the back foot in the opening three rounds as Martinez looked likely to maintain his career record of 24 wins and one draw.
Burns, who brought up win No.29 in the unanimous points victory, was the underdog at Kelvin Hall in Glasgow but the 27-year-old displayed courage to stun the Puerto Rican.
The judges awarded Burns the fight 115-112, 115-112 and 115-113.
Burns graciously paid credit to his entourage for their support in helping him to the world title.
"It was a clean shot, I'll give him that - throughout the fight he did catch us a few times - but as I said before I do have a good chin and I took them well," Burns told Sky Sports.
"I had to grit my teeth every round there and I'm just overwhelmed."
"I couldn't ask for a better camp behind me, the build up to this fight all I could think about was winning this world title, and now it's here I don't know what to say."
A solid right hand was Burns' downfall early, but as Martinez looked for the knockout blow to finish proceedings, Burns fought back in the third round with a flurry of chopping right hand hits that shocked the champion.
Burns then took his momentum into the fourth and fifth rounds, catching Martinez with uppercuts and beating him to the punch with his quick jabs.
Burns copped another big hit in the seventh, but it only shook up the Scot more, and he returned the favour with interest.
The newly crowned world champion topped off the fight with a solid left hook in the final round, that set off celebrations all around the arena for their local hero before the judges confirmed Burns' victory.