Roger Federer made the worst possible start to his claycourt season with an error-strewn defeat against Ernests Gulbis, the nervy Latvian sealing a 2-6 6-1 7-5 win on his seventh match point.

The French Open champion looked to be on his way to a slick seasonal debut on the clay when he took the first set with ease in drizzly conditions, with Gulbis dogged by erratic play.

But the 40th-ranked Latvian cleaned up his act and took advantage as Federer uncharacteristically piled up the unforced errors to notch a run of five consecutive games and win the second.

Federer then saved two match points on his serve in the ninth game of the final set, having been broken in the fifth, before Gulbis wasted four more in the following game.

But the Swiss dropped serve immediately and Gulbis held his to love to claim a memorable victory.