Derek Chisora peeked over the precipice of retirement and blinked. Boxing covered its black eyes as the 42-year-old warhorse declined to confirm that it is 50 fights and out.

Deontay Wilder gave a sigh of relief as victory staved off that decision which all boxers dread. In his reawakened mind there are still world heavyweight titles to be won after 40.

Bless 'em, both. The adrenaline was still pumping a torrent after the exhilaration of a battle royale which offended the snootiest connoisseurs but raised the roof of the O2.

Chisora had promised his family and followers that he would hang up the gloves after Saturday night on the south bank of the Thames. Mrs Chisora, her husband conceded, will have to be consulted yet again. Although he warned her: 'I am addicted to boxing.'

Wilder, the demon puncher whose six-year reign as world champion was ended by Tyson Fury, is eyeing another hot night in London as his gateway to redemption. To that end he fist-pumped the onlooking Anthony Joshua by way of tacit agreement to a late summer showdown of Wembley Stadium potential.

What a difference a fight makes. Two old pros considered to be on their last legs put on the hottest show in town for many a night. The prime candidate for fight of the year, perhaps of this newish century.

It does not take two grand masters of the noble art to make a great fight. Del Boy and Deontay proved that by going at each other hammer and tongs for every one of the 12 rounds. Chisora somehow survived the distance while taking at least double that number of monstrous blows from the American recognised as the mightiest puncher since Mike Tyson. How on earth did he keep punching back?

Classy and stylish, this was not. Thrilling, exciting, blood rousing, compelling, entertaining, unrelenting and brutally phenomenal, it most certainly was.

A throwback to the bare-knuckle days of yore when men o' war stepped up to a line scratched into the ground and stood there battering each other to a bloodied pulp until one of them collapsed.

Despite his protestations that he won the fight, it was Chisora's face that showed the more vivid signs of combat, his legs that wobbled most often and he who was hammered twice through the ropes.

Two of the judges gave it to Wilder by respective scores of 115-111 and 115-113. The third card was 115-112 the other way. A split decision was generous to Chisora. I hate having to tell him after all his valiance but this correspondent scored it 117-111 to the Bronze Bomber, even after allowing for the one point deduction for Wilder for no apparent reason and including two even rounds.

That is not the only reason for supposing that referee Mark Bates was overwhelmed by so wild a brawl and the high-octane atmosphere it generated in the arena. There were plenty of visits to the canvas. So many that he appeared to lose count of how many were punch-inflicted and how many grappled and wrestled to the floor.

Most of us counted two legitimate knock downs by Wilder. Both when Chisora fell entangled in ropes which he criticised as too loose.

His objections to the result were trumped also by incidents that should have cost him the fight before he took all the punishment. He should have been disqualified when one of his corner-men climbed to his aid in the ring during a round. Then again when Mr Bates unforgivably helped him up from the ropes instead of counting over him.

Not that the crowd would have wanted to be deprived of so much as a minute of this thriller.

As he ponders his future, Chisora might consider whether there will ever be a better night to bow out than this. On his shield of bravery but even more so on the rapturous acclaim of his followers that carried him into the night.

The affection for this cult idol of British boxing overflowed into an astonishing moment when his close American buddy Wilder, as he was about to belt him through the ropes, paused to tell him: 'I'm sorry. I love you.'

With friends like this, who needs enemies?