It's impossible to look at the two-word celebration without remembering the frosty past between Federer and Nike.
The celebration of Nadal's achievement is also a case of Nike watching the athlete it sponsors surpass the athlete it used to sponsor.
Federer made a shock move to walk away from Nike in 2018 with reports the company was not willing to budge on a deal that was worth $10 million annually.
What came next has been well documented countless times before.
He was snapped up by Japanese apparel chain Uniqlo on a monster 10-year deal which extends through to 2028 — when he will be 46-years-old — worth a staggering $300 million.
That deal is worth three-times his Nike earnings.
The most fortuitous part of the saga is that Federer's Uniqlo deal was for clothing only — leaving him free to sign a new shoe ambassadorial deal.
His deal with up-and-coming Swisse shoe brand On Running included him being given an ownership stake in the company.
According to sports business guru Joe Pompliano, Federer's deal was worth around three per cent. The company was last year valued at $10 billion, equating to around $300 million for the Swisse Ace.
It breaks down to Federer walking away as the face of Nike from a guaranteed deal of $10 million — and turning it into a deal worth $600 million.
It's impossible to ignore when looking at the Nike billboards plastered around the world right now.
Nike is pushing out Nadal's 'Raging Bull' range hard — even as the headline graphic on its official website in the United States — and why wouldn't they.
The never-ending debate surrounding which player has the right to be considered the GOAT of mens tennis continues to rage without an end in sight, but one can't wonder if Nike would have been so happy to weigh into the debate had Federer never walked away four years ago.
Meanwhile, Djokovic has never endorsed Nike and currently wears Asics shoes for a reported NZ$6m per year.
Nadal, for his part, has continued to side-step all questions surrounding the Big Three's battle for the GOAT mantle — even following his 21st slam.
The victory meant more to him than most of his other grand slam victories, having had to modify his game to compensate for a degenerative bone disease in his left foot that ended his 2021 season last August.
Nadal said during the tournament he thought last year the injury would force him into retirement, making his achievement even more extraordinary.
Federer, who came close to becoming the first to 21 grand slams when he lost in five sets to Djokovic in the 2019 Wimbledon final, missed the Australian Open recovering from knee surgery.
"To my friend and great rival @rafaelnadal, heartfelt congratulations on becoming the first man to win 21 Grand Slam singles titles," Federer posted on Instagram after the match.
"A few months ago we were joking about both being on crutches. Amazing. Never underestimate a great champion.
"Your incredible work ethic, dedication and fighting spirit are an inspiration to me and countless others around the world.
"I am proud to share this era with you and honoured to play a role in pushing you to achieve more, as you have done for me in the past 18 years.
"I am sure you have more achievements ahead but for now enjoy this one!"
