Darren Barker's first defence of his IBF middleweight title ended in defeat after being stopped in the second round by Felix Sturm in Germany.
Former WBO and WBA world champion Sturm made a blistering start to the contest and had the Londoner on the back foot in the first round.
Sturm pressed home his advantage in the second, knocking Barker down twice before his corner threw in the towel with the champion on the end of a barrage of blows.
The German made a positive start landing vicious left hooks and a rapid jab that immediately put Barker on the back foot.
It was a start that nobody anticipated but Sturm clearly intended to make a statement that, rising 35, his career is far from over.
The pace was unrelenting into the second with the home favourite adopting an aggressive approach in a bid to force an early stoppage.
A mean right hook did the initial damage, landing bang on the ear sending Barker to the floor. The Londoner attempted to fight back, but another right high on the temple decked him for a second time.
Barker appeared to be bothered by a hip injury, gesticulating to his corner while getting up from the second knock down.
The fight ended soon after with six straight blows from Sturm forcing Barker's camp to throw in the towel with a minute left in the round.
"Hopefully he is well after he left in pain," Sturm told Sky Sports. "Hopefully he is fine and we can do a re-match next year.
"Always to start fast, that's the best strategy for me. If I start slowly that's not so good for me.
"Darren started a little bit differently to what I expected and had a very good, hard left hook. It was a little bit difficult in the first round.
"Now I'm world champion what can I say. I feel great. I feel at the moment at this age very comfortable. I train very smart and I believe I can box for another five or six years. I'm ready for everything."
It was later confirmed that Barker had dislocated his hip and was quickly whisked away to hospital in a worrying turn of events that could threaten his career, having had both hips operated on in the past.
The Barnet man has undergone surgery on his hips in the past, and speaking to Sky Sports after the fight, trainer Tony Sims said: "It's a disaster - you'll probably never see him in the ring again.
"His hip went in the first round when he threw a right hand. He came back to the corner and said 'I think it's gone, it's hurting me'.
"In the second round he got clipped with a shot and - I don't know what's happened - it's completely gone on him. I was hoping it would just be a muscle injury but when he went down the next time I threw the towel in because I knew he couldn't move.
"He's had problems with his hips before and they're just not right. He'll have an X-ray at the hospital and we'll see what's happening from there."
Barker came close to retiring for good after his world title defeat to Sergio Martinez in October 2011, and his promoter Eddie Hearn reckons it is a "miracle" he returned to win the IBF belt from Daniel Geale earlier this year.
Hearn said: "With Darren Barker every fight is a bonus because his body has gone through the wars. To even get four fights out of him after he came back was a miracle.
Barker is entitled to a rematch with Sturm before the end of next summer, but Hearn said: "If it's as bad as we think it is I'm not sure he's going to be involved in the rematch, and if he's not involved in a rematch I would suggest that would make his decision for him."