Australian Open: Magnificent seven beckons for Federer, Djokovic

Thirtysomethings Roger Federer and Novak Djokovic share the Australian Open record with six wins, but either could make history with a magnificent seventh when the first Grand Slam of the year begins in Melbourne on Monday.

The pair face a stern challenge from youthful force Alexander Zverev, looking for a first major as the torch-bearer for the next generation.

But there are question marks over the fitness of Rafael Nadal and Andy Murray, meaning it remains to be seen if all members of the "Big Four" will again prove a force to be reckoned with.

Twelve months ago Federer rolled back the years once more at the Rod Laver Arena to beat Marin Cilic in five pulsating sets and lift an emotional 20th Grand Slam.

It put him on a par with other six-time Australian Open winners Djokovic and Roy Emerson -- but the Australian great's victories all came before the Open era.

By contrast, the 31-year-old Djokovic endured a miserable early Melbourne exit, followed by elbow surgery and a string of disappointing results that saw him drop outside the top 20.

But since winning a fourth Wimbledon in July the Serb rose inexorably back to number one by losing only three further matches -- one of which was to Zverev at the ATP Finals.

Djokovic won his third US Open in September to put him on 14 Grand Slams -- three behind Nadal and six behind Federer.

Ageless Swiss master Federer, now 37, will remain a chief threat to the Serb but the other two members of the Big Four look to be struggling after an injury-plagued 2018.

Second-ranked Nadal, 32, pulled out of his Brisbane warm-up tournament with a thigh strain although he returned for an exhibition in Sydney and insisted he was healthy.

Murray, 31, looked way below his best in a second-round straight-sets Brisbane defeat to Daniil Medvedev.

- NextGen 'already there' -
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- Competitive at 37 -
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"I played super well in Australia again. So obviously I can't wait to go back there. I'm very proud that at 37 I'm still so competitive."