Tsonga rides luck

Tokyo - Frenchman Jo-Wilfried Tsonga survived a test to beat Latvia's Ernests Gulbis 4-6 6-4 6-3 and advance to the Japan Open semi-finals on Friday.

The world number seven ended the qualifier's resistance by pounding down his 19th ace of the match after a questionable line call had gifted him triple break point in the deciding set.

"Luck is a part of the game," Tsonga told reporters. "It's important to play well but you need some luck to win tournaments. He served unbelievable. It was a surprise for me."

Earlier, Russia's Mikhail Youzhny knocked out defending Tokyo champion Tomas Berdych with a 6-2 7-6 victory.

Youzhny faces former world number one Lleyton Hewitt in Saturday's semi-finals after the Australian pulverised Frenchman Edouard Roger-Vasselin 6-4 6-0 in the day's first match.

Tsonga, who had a punishing run of long matches in Bangkok last week culminating in a semi-final defeat, had to dig himself out of trouble against Gulbis.

He caught a slice of luck when a backhand clipped the tape and appeared to land out to present him with three break points in the final set.

To add insult to injury, Gulbis dropped serve when his own shot clipped the net and floated wide and the Latvian tried to smash a ball out of the arena in annoyance.

Youzhny produced flashes of genius against Berdych, frustrating the fifth-seeded Czech with a clever mix of power and finesse.

Russia's 2002 Davis Cup hero tightened up while serving for the match at 5-4 in the second set and Berdych forced a tiebreak but the Russian took it 8-6 with an ace into the corner.

As Youzhny celebrated by 'shooting' at the crowd with his racquet, Berdych left his in a mangled heap after smashing it on the floor in disgust as he slumped into his chair.

"I stopped playing at 5-4 and was waiting for him to give me the match," Youzhny told reporters. "In Munich (in May) I was 5-1 against Tomas in the tiebreak and lost six points in a row. I didn't want it to happen again."

Roger-Vasselin will want to forget his first ATP Tour quarter-final in a hurry as the world number 189 was blown off court in just 66 minutes by Hewitt.

"I hadn't really seen him play that much," admitted eighth seed Hewitt, whose 2008 season was cut short by hip surgery after the Beijing Olympics.

"He was going for his shots in the first set and it was a matter of hanging in there."