By Nick Mulvenney

MELBOURNE (Reuters) - Fourth seed Robin Soderling eased effortlessly into the last 16 of the Australian Open with a methodical 6-3 6-1 6-4 trouncing of Czech qualifier Jan Hernych Saturday.

"Physically I feel very good," he told reporters. "I haven't spent too many hours on court yet and I'm already in the fourth round, which is very good.

"So I think for me it's a little bit of an advantage."

The Swede racked up 33 winners in the bright sunshine on the Hisense Arena, and it was only repairs to a dead spot discovered on the court at the start of the third set that extended the contest to nearly two hours.

The oldest man left in the tournament, 31-year-old Hernych was playing in the third round of a grand slam for the first time in 19 attempts.

The world number 241 showed some pride with a gallant rearguard action in the third set but Soderling pounded away from the baseline and rarely needed to move out of first gear to keep intact his unbeaten record in 2011.

Next up in the fourth round for Soderling is Ukrainian Alexandr Dolgopolov, who upset France's 2008 finalist Jo-Wilfried Tsonga 3-6 6-3 3-6 6-1 6-1 Saturday.

Looming deeper into the draw, however, are the dominant duo of men's tennis, Rafa Nadal and Roger Federer. Soderling beat one each on his way to the last two French Open finals but then lost to the other in the final.

Seeking to become Sweden's first grand slam champion since Thomas Johansson won at Melbourne Park in 2002, Soderling has confidence that he can beat the top two on the biggest stage.

"I think in every tournament they play, they will be the favorites," he said.

"I already played two grand slam finals and I beat them both in grand slams. But of course they will always be the favorites, and we are the guys who need to play really well if we're going to have a chance to beat them.

"Every match, you know, I will always have a chance."

(Editing by Peter Rutherford)