Haas contemplating early tennis retirement

Veteran German tennis player Tommy Haas may have played his last tournament after suffering a first round defeat at the Kitzbuehel Open.

Tommy Haas is pondering the end of his two-decade tennis career. (AAP)

An unexpected and morale-sapping loss in the first round at the Kitzbuehel Open on Tuesday has veteran Tommy Haas pondering the end of his two-decade career.

The 39-year-old German lost to compatriot Jan-Lennard Struff 6-3 7-6 (7-4) and is now doing some serious thinking about his future.

"It's a terrible feeling. It could well be that this was my last match," one-time ATP No.2 Haas said. "I'm not playing at the level of which I'm capable. That's very disappointing, it's my job to go out there and win matches."

Haas, tournament director at the Indian Wells Masters, has been on a "farewell tour," this season, playing all of the German events and taking wild cards into other tournaments which bring back fond memories.

The veteran, whose career has been plagued by injury and numerous hip and shoulder surgeries, stands just 6-14 on the season, having lost six straight matches since knocking Roger Federer out of the Stuttgart first round two months ago.

"Playing poorly makes it even more difficult to carry on," said Haas, who planned to play through the end of the year.

But his thinking appears to have changed with his recent fall in fortunes.