Maria Sharapova was forced to battle all the way before reaching the last eight of the WTA Amelia Island event.
Russian top seed digs deep to reach the last eight
Maria Sharapova was forced to battle all the way before reaching the last eight of the WTA Amelia Island event.
The top seed, whose only defeat in 21 matches this season came in the semi-finals at Indian Wells, needed to dig deep as Anabel Medina Garrigues threatened a shock.
However, Sharapova clung on to record a 7-6 (7-3) 5-7 7-6 (7-1) victory and set up a quarter-final clash with Alona Bondarenko.
The 10th seed caused an upset by knocking out another Russian, Dinara Safina, 7-6 (7-5) 0-6 7-5.
While Sharapova avoided a shock, the same cannot be said for her fellow countrywoman Anna Chakvetadze.
The 21-year-old second seed, who lifted the Paris title in February, never really got going against Dominika Cibulkova as she crashed out 6-2 3-6 6-1.
Amelie Mauresmo also needed three sets to reach the next stage with the former champion recording a 3-6 7-5 7-6 (8-6) win over Agnieszka Radwanska.
Tough
The win was Mauresmo's first this season against any player in the top-30 and the Frenchwoman was pleased to be through.
"It was definitely a tough one; she has been playing well this year and she is one of the young guns," said Mauresmo.
"When I got up, 5-2, in the third, I think I got a little tight and she wasn't making any errors, but I'm glad I was still able to come in and go for it in the tie-break.
"I think that's what made the difference at the end. I ended the match on a positive note."
American Lindsay Davenport needed one hour, 49 minutes to see off Croatian qualifier Karolina Sprem 6-4 3-6 6-4.
Davenport will now face eighth seed Agnes Szavay after the Hungarian posted a 3-6 6-2 6-3 win over Katarina Srebotnik.
There will be an all-France quarter-final after Alize Cornet and Virginie Razzano both progressed.
Unseeded Cornet saw off Elena Vesnina 6-1 7-5, while No.13 seed Razzano cruised past Olga Govortsova 6-2 6-4.
