Tomic eases path for Nadal

Rafael Nadal overcame a potential banana-skin in the opening round of the Australian Open when Bernard Tomic retired after losing the first set.

The Spaniard won the opening set 6-4 before the Australian called it quits with a thigh injury, to boos from the crowd.

Tomic looked to be in discomfort from the injury and sought courtside treatment throughout the set from a physio.

Despite that Tomic, the world number 57, traded games with the world No 1 until he was broken in the ninth game.

Nadal was sympathetic for Tomic's plight and applauded his opponent as he left the court.

"I am very sorry for Bernard and I hope you get better very soon," Nadal said.

"I know how tough this situation is as I had the same situation a few years ago here on this court, so all the best to him for the rest of the year.

"I saw from the beginning that he had some problems on the leg and he was serving unbelievable in the first couple of games ... it is difficult to comment on a match like this."

Tomic's withdrawal is the eighth of the first round matches in the men's draw.

The final matches on Tuesday saw 25th seed Gael Monfils of France see off American Ryan Harrison 6-4 6-4 6-4, while 18th ranked Gilles Simon came through a marathon match against Daniel Brands of Germany, winning the final set 16-14.

Marin Cilic of Croatia also needed a fifth set decider before he overcame Marcel Granollers 4-6 4-6 6-3 6-3 6-2.