Andreas Beck withdraws with back injury, letting Roger Federer through, while Mardy Fish is highest seed to exit so far
Roger Federer has reached the last 32 of the Australian Open without hitting a ball after Andreas Beck was forced to withdraw from their scheduled second-round clash.
Germany's Beck, who was due to take on the No3 seeded Swiss in the final match of day three on Hisense Arena, had to scratch after suffering a lower back injury.
Federer will now meet the winner of the clash between Croatian Ivo Karlovic and Argentinian Carlos Berlocq in the third round.
Third-seeded Nadal went through 6-4 6-3 6-4 against Tommy Haas of Germany.
Mardy Fish had none of Federer's luck after becoming the highest seed to exit the tournament following his defeat to Alejandro Falla.
American Fish committed 58 unforced errors to help hand his Colombian opponent a 7-6 (7/4) 6-3 7-6 (8/6) victory in exactly three hours.
Having lost the first set on a tie-break, eighth seed Fish became distracted by Falla's use of the trainer and a solitary break handed the world number 71 a two-set lead.
It looked bleak for Fish when he found himself a break down in the third, but he hit back to take it to another breaker only to again find himself on the back foot.
Falla, best known previously for squandering a two-set advantage against Federer at Wimbledon in 2010, looked nervy when wasting his first two match points, the first with a double fault.
But when a third chance presented itself he was grateful for Fish putting a backhand volley wide.
Seventh seed Tomas Berdych eased past diminutive Belgian Olivier Rochus 6-1 6-0 7-6 (7/4), while big-serving South African Kevin Anderson edged out Sergiy Stakhovsky 3-6 6-1 7-6 (7/3) 6-3.
Nadal followed Federer into round three with an impressive 6-4 6-3 6-4 defeat of the veteran Haas.
Haas, 33 and twice a semi-finalist in Melbourne, has seen his career derailed by injury in recent years, but showed flashes of the play which saw him rise to number two in the rankings 10 years ago.
Two early breaks saw Nadal surge ahead and although Haas clawed one back, the Spaniard overcame some nervy moments to take the opening set in 54 minutes.
The second was straightforward with breaks at the start and the end, but Haas put up stronger resistance in the third by claiming a 3-1 lead.
Nadal hit back to level at 3-3 and then claimed the match when Haas missed a forehand at break point in the 10th game.
Afterwards, Nadal was quick to pay tribute to his opponent, saying: "He's a fantastic player. He's had a lot of injuries the last couple of years but it's always great to play Tommy.
"He's thinking about retiring but I thought he played well this afternoon."
Nadal has had his own injury worries leading into the season's first grand slam, injuring his right knee while sitting on a chair on Sunday.
But although it was again heavily taped, the Mallorcan revealed the joint is on the mend.
"It is much better and I am so happy the knee is improving and I am able to play without pain," he said.