DUESSELDORF, Germany -- Germany's Tommy Haas has pulled out of the World Team Cup tournament due to pain in his right shoulder and says he is not sure he will be fit for next week's French Open.

"There is a big question about whether I can play next week," Haas, seeded third in Paris, told a news conference.

"My shoulder is the most important thing and it is very difficult to go out to play in a Grand Slam, where you could be on court for hours, knowing you have a handicap."

Haas said he would undergo more intensive treatment at the weekend. His shoulder is causing pain on forehand shots although not with serves or backhands.

"Perhaps a miracle will happen," he said.

The 24-year-old right-hander said he did not think the injury could threaten his career.

"I am not so negative. I am still young I think it will heal soon. I will do more endurance training," he said.

Haas said he was sorry he had not been able to do more to help his country in Duesseldorf. He did not play on Wednesday when Germany lost to Britain after his replacement Lars Burgsmueller had to retire due to a pulled back muscle.

Germany are facing Spain on Friday for a place in Saturday's final in Duesseldorf. Germany's Nicholas Kiefer lost the first match to Spain's Albert Costa 6-2, 6-2.

Haas stand-in Philipp Kohlschreiber now makes his debut for his country, playing Alex Corretja.

In the other decider on Friday, Britain's Tim Henman beat Russia's Yevgeny Kafelnikov 6-2, 7-6 (8-6). Safin now plays Britain's Martin Lee.