WATCH: All the highlights from a truly astonishing fight as Tony Bellew beats David Haye in massive upset

And just like that the war of words was over.

In the main event in London's O2 Arena, Merseyside's Tony Bellew moved up to heavyweight for the first time for a non-title clash opposite the polarising David Haye. It proved a great idea. The rivalry captured the nation's imagination, with both men taking their promotional obligations seriously and cultivating a very convincing sense of genuine animosity in public appearances. Haye's commitment to the fight-hyping cause came in for some criticism. He received a warning from the British Boxing Board of Control (BBBBofC) early on fight week for his remarks regarding his desire to "hospitalise" his foe. But not a day after that warning came we saw Haye front and centre in Liverpool, referring to the fans at a press conference as "fucking retards." Bellew insisted that Haye's comeuppance would arrive and that's just what happened when they were separated by nothing but a referee. The first round was a frantic affair, with both men clearly letting the emotions of the event get the best of them but they settled into the fight in the second stanza. Haye went headhunting in the third but it was a three-minute spell that was filled with inactivity as Bellew remained content to drag Haye into deep waters while the former world heavyweight and cruiserweight champion eagerly pursued the one-punch knockout. Things started to get very, very weird once the second half of the contest arrived. In the sixth round, Haye clearly picked up an injury to his ankle and, on more than one occasion, he collapsed under his own weight and looked like he had all but given up as he made his way to his stool. https://twitter.com/NextUKFight/status/838165133608239104 The seventh saw Haye's strategy reduced to simply laying on the ropes in the hope that Bellew would punch himself out. And it kind of worked! In the eighth, Bellew's shots began travelling so slowly that Haye was content to drop his hands and accept the jabs on the forehead. Haye, injury and all, was up off his stool first to start the ninth, which was tightly contested. https://twitter.com/jase7t2/status/838166982973358080 Bellew put himself in unnecessary danger at stages in the closing rounds and Haye found the target with his right hand but the 11th round proved that Haye simply couldn't put any weight on his power foot for a second longer. He breached the ropes on two occasions and his corner had seen enough as the towel was sent sailing to the canvas, bringing an end to the war of words. https://twitter.com/FancyCombat/status/838170082366861312 And, as many expected, the pair embraced after the final bell. Fair play to David Haye for fighting through the pain barrier. Fair play to Tony Bellew for the upset. And fair play to both men for putting their differences aside to hug it out in the centre of the O2 Arena. Boxing, eh? Bloody hell!

This article originally appeared on JOE.co.uk.