Maria Sharapova cruised through to the semi-finals of the 2013 Mutua Madrid Open, but Serena Williams was given a stern test in the quarter-finals on Friday.
Serena and Sharapova are at the centre of attention at the WTA Madrid this week as they do battle for the No. 1 ranking spot.
Williams was pitted against Anabel Medina Garrigues in the quarter-finals and what looked like a straightforward win on paper turned into a real scrap. Amazingly, Serena was bagelled in the second set before fighting back for a 6-3 0-6 7-5 win.
Sharapova had no such problems, as she took down Kaia Kanepi in straight sets. The Estonian produced some great performances in the early stages in Madrid, but was no match for the world No. 2, who won 6-2 6-4.
Open the slideshow above for the best pictures from Friday's quarter-finals!