Melbourne – Top seed Rafael Nadal eased through to the second round of the Australian Open after local hope Bernard Tomic retired with an injury after the first set on Tuesday.

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 Spanish world number one until he was broken in the ninth game.

As soon as Nadal served out for the opening set, Tomic said he could not continue further and retired from the match.

The announcement was greeted with a smattering of jeers from the capacity Rod Laver Arena evening crowd.

Nadal was sympathetic for Tomic's plight and clapped the Australian 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.”

Nadal, who missed last year's Australian Open with knee trouble, will play another Australian Thanasi Kokkinakis in the next round. – Sapa-AFP