Swiss world No.2 Roger Federer survived a serious challenge from Daniel Gimeno-Traver of Spain to edge into the semi-finals of the Istanbul Open after a three-set battle lasting almost two-and-a-half hours.

Gimeno-Traver, 29, the world No.62, was in no way overawed by the occasion as he met Federer for the first time with the Swiss eventually pushing through to win 7-6 (7-3) 6-7 (5-7) 6-3 on Friday.

Federer showed exquisite touch at times but the Spaniard put up strong resistance.

The 17-times grand slam winner was kept in place in a tight first set, only moving ahead in the tie break which he took with a gorgeous backhand crosscourt dink that ravished the crowd.

Playing with aggression and abandon, Gimeno-Traver raced to a 5-2 lead in the second set but Federer pegged him back to force another tie-break.

Against the odds, Gimeno-Traver raised his game once more with some impressive shot making, taking the breaker 7-5 when Federer tamely pushed a service return into the net.

But Federer showed his class in the final set, taking it 6-3.