MADRID (Reuters) - American qualifier Robby Ginepri knocked out fifth seed Nikolay Davydenko 4-6 6-4 6-4 in the second round of the Madrid Masters on Wednesday.

The defeat is a major blow for the Russian, who is chasing one of the four remaining places in next month's eight-man Masters Cup in Shanghai, as it came hot on the heels of his quarter-final exit from the Kremlin Cup.

In the next round Ginepri will meet Frenchman Gilles Simon, who put out 11th seed James Blake on Tuesday.

Frenchman Jo-Wilfried Tsonga, the 16th seed, narrowly avoided a similar fate to Davydenko, winning a third set tiebreak to beat the impressive Marcel Granollers 3-6 6-3 7-6.

A spectacular leap and overhead backhand volley allowed him to break back and level midway through the third set, before he forced the Spaniard into an error to take the tiebreak 7-5.

Later on Wednesday, second seed Roger Federer plays Czech Radek Stepanek, and defending champion David Nalbandian faces Czech Tomas Berdych.

(Writing by Mark Elkington, editing by Pritha Sarkar)