Greg Rusedski believes that Roger Federer's best chance of winning a 21st Grand Slam title comes at Wimbledon, rather than the Australian Open.
The Swiss veteran has not played a tour-level match since losing to Novak Djokovic in the last four in Melbourne in January, with two knee surgeries ruling him out of the remainder of the season.
Federer won in Australia in 2017 and 2018 but Rusedski, a former US Open finalist turned commentator, believes that Djokovic will be too big an obstacle to overcome.
"I don't think he's got a shot to win the Australian Open or the French, those will be big asks for him. He can still have good runs there but won't win them," he told the Daily Express.
Wimbledon, that's where he's aiming at. He's won eight titles there. The points against Novak, that must be the most heartbreaking loss of his career.
However, Rusedski believes that a win in Melbourne, which would give Federer the outright lead in the Grand Slam tally with 21, could prove a decisive blow in the three-way battle with Rafael Nadal and Djokovic to end up on top.
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"[If he wins that] All of a sudden that takes him to 21 and leaves Djokovic right now at 17 and he's still ahead in the race over Nadal.
"One match or one point can make such a big difference to somebody's career - trust me I know about these things!"
Federer turned 39 in August and would become the oldest man to win a Grand Slam in the open era should he lift a major in 2021.