Agassi puts Federer's Aus Open above Nadal's 'La Decima'

Andre Agassi says Roger Federer's incredible victory at the 2017 Australian Open is harder to comprehend than Rafa Nadal's nine French Open titles.

Nadal is on track for a record 10th title at Roland Garros, dropping just 20 games on his way to the quarter-finals, just shy of his own record of 19.

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While Agassi acknowledges the magnitude of Nadal's feat, the tennis legend says Federer's efforts at Melbourne Park in January are too hard to quantify.

"This is one of those scenarios where the statistics alone put Nadal's French Open achievements into perspective," the eight-time major winner said in Paris on Monday, where he is coaching Novak Djokovic.

Nadal and Federer at the Australian Open. Image: Getty

"To win the French Open once is a herculean performance - he's trying to win it for a 10th time.

"It's just remarkable.

"I think the harder thing to put into perspective is what Federer accomplished in Australia.

"I mean six months away from the game, the competition and at his age (35) and he goes out there and wins the way he did with multiple five-setters.

"That's a little bit harder to tangibleise (sic) but winning 10 times - winning nine times, forget about 10 times - all you have to do is write that down on a piece of paper.

"It puts into perspective."

Nadal has capitalised on Federer's absence at Roland Garros, equalling a remarkable French Open feat set by the Swiss great.

Nadal made an emphatic statement on Sunday, smashing Roberto Bautista Agut in their round of 16 match.

In doing so the Spaniard reached a record-equalling 11th Roland Garros quarter-final, matching Federer's mark for last-eight appearances in Paris.

Nadal hasn't lost a set so far this tournament, and is on track to win the title without doing so, something he did in 2008 and 2010.

Only Bjorn Borg (1978 and 1980) and Ilie Nastase (1973) have also achieved that feat.