Michael Bisping was one of three champions to have their belts ripped away from them in the Octagon at Madison Square Garden.
The 38-year-old lost his Middleweight strap inside three rounds at UFC 217 as legendary fighter Georges St-Pierre forced a technical submission with a rear-naked choke.
The "Count" is now staring retirement directly in the face after losing the second defence of his prized title in New York City.
The mixed martial artist, from Clitheroe, demonstrated drive, determination and durability in landing a shot at the top last summer and those attributes were characterised once more as Bisping lost consciousness in the finish in his refusal to tap out.
The former champion, who was dethroned alongside Cody Garbrandt and Joanna Jedrzejczyk, was seemingly in control at the midway point as his Canadian opponent struggled for breath.
But the three-time Welterweight king, returning from a four-year hiatus from the organisation, stood up to the challenge of climbing up a weight class to take Bisping's crown.
The pair traded blows in the opening rounds, though it was Luke Rockhold's conquerer that appeared the more settled of the two as GSP failed to trouble Bisping on the deck.
Indeed it was the challenger who returned the more bloodied of the two following a takedown in the second stanza and it seemed as though he'd failed to capitalise on another ground-and-pound in the third after knocking his foe down with a crippling left hook. However, St-Pierre's artistry and experience showed.
The 36-year-old, who holds the record for most wins in title bouts and the second longest combined title streak in UFC history, lured Bisping in to a false sense of security before switching to the rear and turning out the lights on his reign.
And in doing so, St-Pierre joined an elite list of fighters alongside Randy Couture, BJ Penn and Conor McGregor to have held titles in two different divisions.
Bisping, the UFC's first ever British world champion, who had previously defended his title against Dan Henderson, told FOX Sports: "This is a difficult sport. Respect to Georges. He beat me tonight. One team wins and one team loses.
"Tonight was his night. I thought I was doing well. He caught me with a good shot and wobbled me. He was strong. God bless him. Good for him.
“When you win, you go celebrate, and when you lose you drown your sorrows. Look, at this point, this is my hobby. I get paid well to do what I do. I’m bummed.
"I remember what it was like to be world champion – like it was yesterday. Georges is a good man. I was trying to sell pay per views."
Bisping, talking to Dana White in the aftermath, added: "Georges was the better man and it's a hell of a squeeze that he's got there. You've got to give it up for Georges.
"Thank you to everyone who has supported me throughout my career. Thank you so much. My wife and children - if it wasn't for them I wouldn't be here right now.
"Thank you all. I'm not done, I know I spoke about retirement but Georges was the better man and it's as simple as that. There are no excuses."