World sport's most intense individual rivalry takes on even greater significance when Rafael Nadal begins his holy grail quest for yet more tennis history at the Australian Open starting on Monday.
Swiss superstar Roger Federer will be defending much more than his title when he launches his bid for an open-era record fifth crown at Melbourne Park on Monday against the luckless Lucas Lacko.
Federer leads Nadal 16 to nine in the grand slam stakes but should the Spaniard win the Open to become the first man since Rod Laver in 1969 to hold all four major trophies, he will also reopen the age-old "greatest ever player" debate.
The two tennis titans have dominated the sport like no other pair before them, facing off in an unprecedented seven grand slam finals and monopolising the world No 1 ranking for the past seven years.
In most eyes, the Artful Roger rightfully holds the "greatest-ever" tag, but the Majorcan Marvel is rapidly closing in.
Both their numbers are staggering.
Since Nadal broke through at the 2005 French Open, he has stacked up nine grand slam titles to Federer's 12.
The rest of the world have tallied a measly two.
During the same five-and-a-half-year period, Federer has won 29 tournaments to Nadal's 37.
Federer has topped the year-ending rankings three times since 2005 and Nadal twice.
Even Nadal can barely believe what the Swiss-Spanish alliance have managed to achieve.
"That's something that's going to be not easy to repeat," he said on Sunday after teaming with his great rival on Sunday during the Rally for Relief charity event at Melbourne Park.
"I don't know how many tournaments, but in more than 20 grand slams, only two or three players won grand slams. I think that's impossible to continue like this."
Where it matters most, Nadal leads Federer 6-2 head-to-head in their grand slam series and has prevailed in five of their championship finals on the game's biggest stages.
The Spaniard was 25-1 in the majors in 2010, his lone defeat a mid-match quarter-final retirement against Andy Murray at the Australian Open.
Incredibly, he recovered from his chronic knee injuries to win a fifth French Open, second Wimbledon title and his maiden US Open to complete the career grand slam.
Now the 24-year-old is poised to become the first man in history to achieve a non-calendar-year grand slam sweep - or the "Rafa Slam", as it's been touted.
"He's been playing incredible," Federer marvelled on Sunday.
"An incredible run through the French, sort of the clay (court events), Wimbledon, US Open. It was incredible to see.
"Then obviously it's hard to maintain. But he's going to be for sure ready for this. I'll follow it very closely. If I get a chance, I hope I can stop him."
If he can't, Federer may soon find himself playing catch-up to Nadal in the "greatest-ever" debate. Who would have thought.
Tellingly, Federer was at his most prolific between the age of 24 and 26, landing eight of a possible 10 majors during a remarkable two-year stretch from 2005-07 - and losing the other two grand slam finals to Nadal at Roland Garros.
On that basis, Nadal is only now reaching his peak.
Along with Federer, 2008 Open champion and this year's third seed Novak Djokovic also plays his first-round match on Monday - against Marcel Granollers, while eighth seed Andy Roddick takes on Jan Hajek.
Nadal opens on Tuesday against Brazilian Marcos Daniel.
- AAP
Tennis: Federer defending more than Aussie Open title
Defending Australian Open champion Roger Federer. Photo / Getty Images
AdvertisementAdvertise with NZME.