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By Martyn Herman
PARIS, June 3 (Reuters) - There is not much of Tommy Haas's body that has not had a visit from the surgeon's knife.
Shoulders, elbows and hips have all needed urgent attention at various times yet, at 35, the patched-together German is playing some of the best tennis of his life and has reached the quarter-finals of the French Open for the first time.
On Monday the former world number two outclassed Russia's Mikhail Youzhny 6-1 6-1 6-3 to become the third oldest man to reach the quarters at Roland Garros in the professional era and the oldest since Istvan Gulyas in 1971.
There have been plenty of dark periods in his 17-year career, most notably in 2002 when his parents were involved in a serious motorcycle accident that left his dad in a coma.
That is why Haas does not take his sport too seriously and is making sure he basks in the Indian summer of his career.
"It's been a great ride," said the 12th seed, who faces world number one Novak Djokovic next. "I feel like I'm riding a wave that I hope to continue as long as I can.
"I won't be doing this for another five to 10 years.
"I was maybe at my peak at the end of 2001, at 23 or 24 maybe, looking ahead to what goals I could achieve.
"Now it's more like happy to still be part of it, happy to be in these situations, happy to be on the big stages and playing against the best in the world.
"It's the most fun I've had, the most enjoyable time, that's for sure."
Haas has reached the last eight for the first time at the 12th attempt. He is also the first German to do so since 1996 and the oldest player to reach the quarters of any slam since Andre Agassi at the 2005 U.S. Open.
He is not the only member of the over 30s club to be impressing at this year's French Open. Five players aged 30 and over reached the last 16, the highest total since 1983.
"Obviously a couple of the guys like Roger Federer and David Ferrer are two of the best players," Haas said having only just got fresh shirts in time for the Youzhny clash after handing in his laundry late.
"I think we are all a bit smarter about how to train, how to eat, dealing with recovery.
"The physical and fitness areas have improved a lot in sports in general and that's why so many players in their early and mid 30s are doing well."
As well as Haas, Federer, Ferrer and 30-year-old Youzhny, Spain's Tommy Robredo, aged 31, has shown iron-man endurance to reach the quarter-finals having recovered from hopeless-looking two-set deficits in his last three rounds - the first time that has happened since 1927.
Like Haas, Robredo is appreciating the ups more after also needing surgery to resurrect his career.
"You learn a lot more from the downs than the ups," said Robredo, who faces 31-year-old Ferrer on Tuesday.
"When you're back, you're even happier. Maybe some years ago I wouldn't have fought for each point."
Two years ago, when Haas made his comeback from hip and elbow operations, his ranking had slumped into the 300s and he lost to a qualifier as a wildcard in the first round of the French Open.
Now he is relishing a first Roland Garros quarter-final against Serbia's Djokovic.
"Two years ago, who would have thought I would be in this position. Almost no way. I didn't have to worry so much financially and I could live a good life." he said.
"But something in me said, 'You know what? I can still maybe do something'. I'm happy I made that choice." (Editing by Mark Meadows)