Three-time Grand Slam champion Stanislas Wawrinka, seeded ninth in Melbourne, will take on unseeded Richard Berankis in the first round.
"I didn't know what was going to happen but we did some treatments and gave it a lot of thought and luckily for me I'm here".
"Rafa and Roger are the best ones, but I'm playing well and I'm in good shape".
Federer, who is fresh off securing a third Hopman Cup title for Switzerland, is eyeing a sixth Australian Open crown in Melbourne this month. He also has No. 7-ranked David Goffin, Juan Martin del Potro, Sam Querrey, and Milos Raonic in his quarter.
Djokovic has not played since his quarter-final exit at Wimbledon as a result of a persistent elbow injury.
Muguruza's preparations for the first grand slam of the year have been similarly thrown into disarray after she was forced to withdraw from the Sydney International with a leg injury.
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The Intel exec said users shouldn't feel discouraged by these snags and continue to install updates from OS makers and OEMs. The security patches by Nvidia relate to software drivers that let its chips work with operating systems like Windows.
Serena Williams has opted not to defend her title four months after giving birth to her first child, leaving the women's draw open.
The Serena Williams pregnancy story is already fantastic - but if the 23-time grand slam winner's 2018 plays out as hoped, the story is going to be completely remarkable. "Also, I got a great opponent today, the No. 5 in the world, so it was a fantastic test for me to see where I am".
Novak Djokovic has practised behind closed doors ahead of next week's Australian Open, adding to the intrigue surrounding his return from a lengthy injury layoff.
A magical 20th slam might seem a formality for a player who did it all in last year's tournament with the shortest of run-ups, but on closer inspection, Federer's path through the draw is far from straightforward.
It has meant some alterations to the draw, but tournament director Peter Johnston said it was worthwhile. She arrives in Melbourne in good form, having just won a tournament in Brisbane.
"The drive, I still have it".
"It doesn't help when someone wants to walk on the court and get straight back off - that mental state doesn't help", she said.
Djokovic continued: "I'm still not 100 per cent".