Ageless Tommy Haas Upsets Stanislas Wawrinka to Enter Rome Masters Quarters

The seemingly ageless Tommy Haas upset third-seeded Stanislas Wawrinka 5-7, 6-2, 6-3 Thursday to reach the Italian Open quarter-finals. (Click here for latest on Tennis)

The oldest player in the draw at 36, Haas used his expertise to give Wawrinka trouble with heavy topspin on the red clay courts at the Foro Italico.

Haas hadn't beaten a top-10 player since taking out then No. 1 Novak Djokovic in Miami more than a year ago. "These things don't happen too often anymore so I still take them and I'm really proud of them," the German said. (Also read: Bopanna-Qureshi knocked out)

Wawrinka cited a back injury that occurred in colder conditions during his opening win over Spanish qualifier Pere Riba. "I couldn't move too well," he said. "It's really nothing serious. It's just painful and I need some rest - maybe a few days."

Elsewhere, eighth-seeded Milos Raonic beat 11th-seeded Jo-Wilfried Tsonga 7-6 (5), 6-4.

In the women's tournament, 11th-seeded Ana Ivanovic took out two-time Rome champion Maria Sharapova 6-1, 6-4.

Second-seeded Li Na defeated Australian veteran Sam Stosur 6-3, 6-1 and will next meet 10th-seeded Sara Errani of Italy, who kept the crowd content by beating Czech qualifier Petra Cetkovska 6-4, 7-6 (3).

And third-seeded Agnieszka Radwanska eliminated Francesca Schiavone 6-4, 6-1.

The 15th-seeded Haas broke Wawrinka to take a 5-3 lead in the third set with a series of deep spinning shots which eventually prompted Wawrinka to miss a forehand.

Haas then served it out with an ace down the middle on his first match point.

Haas committed just 17 unforced errors to Wawrinka's 40.

Wawrinka has had a solid year by winning the Australian Open and the Monte Carlo Masters but he also had an early exit in last week's Madrid Open - leaving his form in question as he enters Roland Garros in 10 days.

Haas was a Rome finalist in 2002, losing the title match to Andre Agassi.

"He's a really good player," Wawrinka said. "He has a good serve, he can come to the net and he has touch. We all know how he (plays). He's been there for a while."