Stanislas Wawrinka has booked his place in the semi-finals of the Madrid Open with a hard-fought win over Jo-Wilfried Tsonga across three sets.

The Frenchman got off to a sluggish start and was broken twice within the opening four games without reply.

Tsonga did hit back to make it 5-2, but the Swiss number two went on to break his opponent's serve for a third time and comfortably take the opener 6-2.

The two competitors were inseparable in the second set, with Wawrinka first to break for 3-1, only for Tsonga to find his form and break back immediately and make it 3-2.

Neither serve faltered for the remainder of the second, and a tie-break ensured, which was no less close than the set that preceded it.

Wawrinka squandered three match points during an intense breaker, with Tsonga pulling off a magnificent save with his back to the net at 8-9, and going on to seal it 11-9.

The deciding set was also fiercely contested, but Wawrinka's break at 2-2 proved decisive, allowing the world number 15 to serve out the game at 5-4.

Wawrinka will take on Tomas Berdych for a spot in the final.