Victoria Azarenka lets Serena Williams off the hook

Victoria Azarenka spurned three match points as she fell to a 7-6 (7-5) 3-6 7-6 (7-1) defeat against top seed Serena Williams at the Madrid Open on Wednesday.

The Belarusian produced a stunning third-set fightback to give herself hope of a quarter-final berth in the Spanish capital but failed to convert at the crucial moments.

Having shared the opening two sets, world number one and two-time Madrid champion Williams was well on course to see out the win having moved 3-0 ahead in the decider.

While Azarenka recovered to lead 6-5, she wasted three match points in the penultimate game as her hopes of a fourth career victory over the American faded.

Azarenka - who surrended a 5-1 lead in the first set tie-break - was blown away in the latter stages as Williams reeled off the final five points to seal a 26th consecutive victory and set up a last-eight clash with either Carla Suarez-Navarro or Ana Ivanovic.

Defending champion Maria Sharapova was also given a stern test by France's Caroline Garcia before progressing 6-2 4-6 7-5.

Sharapova was beaten by Garcia for the first time in Acapulco earlier this year and hopes of a repeat result looked very much alive during a close-fought third set.

Having shared the opening two sets, Garcia matched Sharapova for much of the latter stages until the third seed claimed a crucial break in the 11th and saw out the victory.

The Russian will face Caroline Wozniacki in the quarter-finals after the world number five beat Agnieszka Radwanska 6-3 6-2.

In the clash of the fellow seeds, Wozniacki broke six times during the 82-minute match to record a third consecutive victory over the 26-year-old Pole.

Elsewhere, fourth seed Petra Kvitova eased past Anastasia Pavlyuchenkova 6-1 6-4, while Irina-Camelia Begu and Lucie Safarova enjoyed victories over Roberta Vinci and Barbora Strycova respectively.

Svetlana Kuznetsova overcame Samantha Stosur in the final match of the day, coming from a set down to triumph 5-7 6-2 7-6 (7-5) in two hours, 44 minutes.