Tommy Haas has had to pull out of the Davidoff Swiss Indoors tournament in Basle after contracting swine flu.

The 31-year-old consulted his doctor when he contracted flu-like symptoms, and he was diagnosed with the highly-contagious H1N1 strain.

"I did a test because I suspected I had the swine flu and the test was positive," he told the Bild newspaper.

"It was obviously a shock for me."

Nevertheless, the German, who reached this year's Wimbledon semi-finals, is not too worried about the illness, even if it means his season is practically over.

"I am quite relaxed because I know that swine flu is a particularly strong form of flu, but when you are in a good physical condition like I am, then you can quickly beat it off," he added.

Haas had to pull out of the last ATP event in Stockholm after detecting the flu-like symptoms and he is unlikely to be fit to appear in Paris next week.

"It was really bad for three days and I couldn't leave my hotel room," he revealed. "I felt really bad."