HALLE, Germany (AP)—Roger Federer got off to a solid start with a 6-4, 6-4 win over Jarkko Nieminen of Finland in the first round of the Gerry Weber Open on Tuesday.

Playing his first match at No. 2 after Rafael Nadal returned to the No. 1 spot by winning the French Open, Federer was forced to work hard to earn the victory.

Federer will play the winner of the rain-delayed match between Noam Okun and Alejandro Falla. The match will be completed Wednesday.

The Swiss star, preparing to defend his Wimbledon title later this month, was happy to be playing on grass again.

“I think any surface change has something nice about it, but grass obviously is the most special one because you are only one month on it, so every day you have the chance to play on this surface is a special day,” he said. “I feel it is something you want to savor as long as you are on the surface.”

Mikhail Youzhny became the third seeded player to be knocked out of the tournament after losing to German wild card Nicolas Kiefer 4-6, 6-1, 7-5. Kiefer had 19 aces.

The 32-year-old Kiefer received a wild card invite for Wimbledon on Monday, and said that motivated him against the 14th-ranked Youzhny.

“That was great news,” Kiefer said. “Wimbledon is a highlight—it’s the best tournament in the world and I am really pleased to get a wild card.”

No. 2 Nikolay Davydenko defeated Simon Greul of Germany 7-6 (1), 6-0 and said he was satisfied with his first competitive match since breaking his left wrist in March.

“After three months out, it was hard to come back,” he said. “Training is nothing like matches, and I was so tired out there—my legs were so heavy.

“But after winning the tiebreak, I was less nervous and just got better and better. I am slowly getting my self-confidence back and I still hope to get back to the highest level.”

Also, Philipp Kohlschreiber beat Ruben Bemelmanns of Belgium 7-6 (2), 6-7 (10), 6-4.