Ukraine’s Alexandr Dolgopolov produced a stunning five-set victory over fourth seed Robin Soderling to reach the Australian Open quarter-finals on Monday.

The pony-tailed Dolgopolov, resplendent in pea-green shirt and shirts, completed a shock 1-6 6-3 6-1 4-6 6-2 win to become only the second man from his country to reach the last eight of a grand slam.

“I play relaxed. You know, I enjoy tennis,” Dolgopolov told reporters after the biggest upset so far of the year’s first grand slam. “I don’t get tight too much. I play really freely.

“Sometimes it pays off. I have fun. I try to fight every point, do the right things.”

Soderling, French Open runner-up the past two years, had been viewed as a serious contender in Melbourne, having won in Brisbane and not dropped a set in eight matches in 2011.

It looked to be plain sailing for the Swede after a simple first set but Dolgopolov tore through the next two sets to rattle Soderling.

Blister Trouble

Soderling, who needed a medical timeout in the fourth set to treat blisters on his foot, dug deep to level a cliff-hanger fourth round match.

However, he was quickly staring down the barrel in the deciding set, Dolgopolov drilling another big forehand past the Swede to break for 3-1.

The 23-year-old was making only his fourth grand slam appearance but held his nerve to record his first win over a top 10 player and he now faces fifth seed Andy Murray for a place in the semi-finals.

Dolgopolov, the first man from Ukraine to reach a grand slam quarter-final since Andrei Medvedev in 1999, acknowledged Murray was in awesome form.

“For sure he doesn’t give you any cheap points,” he said. “I just watched the first set. He had like two unforced errors. It’s really tough to play him.”

Soderling offered no excuses.

“I never underestimate anyone,” said the big Swede. “I didn’t play good enough. Simple as that. I had a blister on my toe, but it’s nothing serious.

“My two biggest weapons are my serve and my forehand. They were not weapons today.”