Monte Carlo - Roger Federer lost for only the third time in his career to a compatriot, going out to Stan Wawrinka 6-4, 7-5 on Thursday at the Monte Carlo Masters for his earliest clay exit in five years.

Wawrinka played to his own strengths on his favourite surface to leave his second-seeded Davis Cup team-mate and fellow Olympic doubles gold medallist flat-footed in the third-round defeat in one hour, 50 minutes.

"It was maybe not the most spectacular tennis, but it's my most beautiful victory," said Wawrinka, finalist in Rome last May. "I need to believe in my game, I knew I can play very well on clay court, and hard court, too."

The loss was the earliest on clay for the 13-time Grand Slam winner since going out in the Roland Garros third round in 2004. Federer now stands 9-3 against compatriots following two losses in 2000 to Marc Rosset.

While defeat had to be bitter for a man without a title since October, Federer was just slightly consoled by the fact that he lost to one of his best friends in the game.

"I'm happy for him that he's progressed so much over the last couple of years," Federer said of the 13th seed who next plays Andreas Beck after the German qualifier defeated Juan Monaco of Argentina 3-6, 6-2, 7-5.

"He's finally making a push, you know, getting close to top players and beating top players like myself. I think it's great for him."

Spain's Fernando Verdasco got an easy victory on a day when play was delayed for five hours due to rain as he defeated Spanish compatriot David Ferrer 6-2, 6-1.

Federer was well off his game against his good friend, as Wawrinka won for the first time in their series after two ATP defeats. Federer will hit the practise court next week to work on his serve with the Rome Masters starting April 27.

"Not that I expect 10 aces a set here on this type of heavy clay, but I just think it's something I need to work on, make sure my timing gets right, my footwork gets right, and my forehand, that I use it the right way."

Federer's defeat was his earliest at the principality since going out in the 2002 second round to David Nalbandian.

The Swiss has played the last three finals, losing them all to Rafael Nadal, who managed to get in one game to trail Ecuador's Nicolas Lapentti, 1-0 before evening rain forced the pair off court.

Wawrinka has limited knowledge of quarter-final opponent Beck. "I know him a little bit. I haven't seen him here, but I know he's talented and he hits hard. He's a left-hander and I must be solid against him."

Other seeds also stalled as Novak Djokovic split with Spaniard Alberto Montanes 6-1, 6-7 (4-7) and Scot fourth seed Andy Murray fought through a 13-11 tiebreaker with Italian Fabio Fognini before rain interrupted their second set on serve 1-0 to Murray. (dpa)