The 31-year-old top seed has not won a single trophy this season but is still the all-time most successful player in the Halle ATP tournament's 20-year history.

Federer won it for the first of five times in 2003, the same year he landed his first Wimbledon title.

"I would like to lift my first trophy of the season in Halle . . . it would give me a confidence boost," said the Swiss master.

However, his doubles campaign came to an abrubt elimination on the tournament's opening day when he and partner Tommy Haas of Germany were defeated by 2010 Wimbledon champions Jurgen Melzer of Austria and Germany's Philipp Petzschner 7-6 (7/3), 6-4.

"It was a real pleasure but a shame we lost," said Federer, who was playing his first ATP doubles tournament since Indian Wells in 2011, where he linked up with his compatriot Stanislas Wawrinka.

"But Jurgen and Philipp played very well and made very few mistakes:"

Along with Wawrinka, Federer won his only Olympic gold medal when the Swiss team won at the 2008 Beijing Games.

Haas, who defeated Federer during last year's singles final, said their lack of preparation was decisive in their elimination.

"It was very special to play with Roger because we've known each other for such a long time," said the 35-year-old veteran.

"But you could see we hadn't had much practice together." 

Federer once owned the Halle singles tournament, winning it four years in a row before he withdrew due to fatigue in 2007.

He won again in 2008, his fifth success, but his two appearances since then have seen him beaten in the final both times, by Lleyton Hewitt in 2010 and Haas, who he could potentially meet in this year's semi-finals if all goes to plan, in 2012.

The world number three's surprise quarter-final exit at Roland Garros last week to France's Jo-Wilfried Tsonga, is not playing on Federer's mind.

"Paris has little influence on the way to play in Halle or Wimbledon," he said before insisting that "the second half of the season will be better than the first".

Since winning his first ATP tour title in Milan in February 2001, Federer has never had to wait so long to break his trophy duck in any individual year.

The last time he almost went this long was in 2009 when he took until mid-May to win his first trophy, beating Rafael Nadal in the clay Madrid Masters final.

However, that year he went on to win Roland Garros for the first and only time, as well as a sixth Wimbledon crown, which he has since added to with a seventh.