Rome, May 10:

World number one and top seed Roger Federer was sensationally knocked out in the third round of the Rome Masters by Filippo Volandri on Thursday.

A two-time beaten finalist here and the reigning Australian Open champion, Federer uncharacteristically made 44 unforced errors in his shock 6-2, 6-4 defeat to the Italian wildcard ranked 53rd in the world.

Defeat means Federer has now gone four tournaments without winning a title, his longest stretch without a trophy since he became world number one in February 2004.

Earlier on Thursday American third seed Andy Roddick was bundled out 6-0, 6-4 by Argentina’s Juan Ignacio Chela. Roddick, a semi-finalist here in 2002, struggled with his serve and made 27 unforced errors as Chela recorded only his second victory over the former world number one in eight meetings.

Ranked 23 in the world, Chela will now face the winner of the all-Chilean clash between sixth seed Fernando Gonzalez and Nicolas Massu. Roddick admitted he gave himself too much to do after his poor first set display.

Chela, who has never reached the Rome quarter-finals before, was delighted with his performance at the Foro Italico.