'Not human': Shock photo of Rafa Nadal emerges after Aus Open final

Even after spending five hours and 24 minutes on court in his five-set war with Daniil Medvedev on Sunday night, Rafa Nadal was on the exercise bike cooling down and taking every precaution to prevent injury.

Nadal admitted to being "physically destroyed" after coming back from two sets down to stun Daniil Medvedev and claim a record 21st grand slam title.

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It was the first time in 15 years that Nadal has won after falling into a two-set hole at a grand slam, prevailing 2-6 6-7 (5-7) 6-4 6-4 7-5 in a drama-charged climax to the Australian Open at Melbourne Park.

The sapping encounter was the second-longest final in Australian Open history, behind only Nadal's five-hour, 53-minute loss to Djokovic in 2012.

Startling post-match footage has since emerged of the moment Nadal collapsed in a heap on the locker room floor surrounded by his coaches and trainers.

He skipped the traditional studio interview with Channel Nine because he was so exhausted, but was still made to go through his cool-down routine with his trainers.

Footage shows Nadal on the exercise bike in the bowels of Rod Laver Arena before being greeted and congratulated by Aussie legend Rod Laver.

Nadal then collapsed in exhaustion on the floor as the gravity of his achievement began to sink in.

“Nadal hugs everybody in his team - including Marc Lopez who is already in a Rafa 21 shirt - and then collapses to the floor with exhaustion," tweeted Ben Rothenberg.

"Eventually he’s persuaded to get on a bike to cool down, which he, amazingly, is able to do.”

Rothenberg later wrote: “Nadal is still on the bike, by the way. He’s not human.”

Rafa Nadal's insane comeback in Aus Open final

In claiming the Norman Brookes Challenge Cup for the second time and 13 years after his first, Nadal also joins Laver, Roy Emerson and Djokovic as only the fourth man in tennis history to win each of the four grand slam titles at least twice.

"Without a doubt, it's one of the most emotional moments in my tennis career," Nadal told the crowd.

"I'm going to keep trying my best to come back next year."

Laver enjoyed a front-row view in the arena named in his honour as his fellow southpaw pulled off one of the most incredible wins of his legendary career.

Seemingly on the canvas after dropping the second set from 5-3 up, Nadal somehow conjured his first escape from two sets down since beating Mikhail Youzhny in the Wimbledon fourth round in 2006.

Youzhny, though, wasn't the World No.2, reigning US Open champion and riding a 13-match grand slam winning streak like Medvedev.

Even more remarkably, Nadal had only played two matches between last June and January because of a crippling foot injury and remained in doubt for the Australian Open until after Christmas.

Asked in his post-match press conference if he now felt he was the greatest men's player of all-time, Nadal was typically humble.

"Of course, I know it's a special number, 21," he said.

"I feel honoured, lucky to achieve one more very special thing in my tennis career.

"But I don't care much if I am the one, or not the one, or the best of the history, not the best of the history.

"Honestly, today I don't care much, no? For me it's about enjoying nights like today. That means everything for me."

with AAP

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