Leander Paes and Nenad Zimonjic of Serbia and Montenegro entered the semi-finals of the Madrid Masters beating Mahesh Bhupathi and Martin Damm of the Czech Republic 7-6(3), 7-5 on Friday.

The victory enhanced Paes and Zimonjic's chances of qualifying for the season-ending Maters Cup in Shanghai. The pair is currently sixth in the ATP Doubles Race.

In a close match, both teams traded breaks early in the first set. Paes and Zimonjic had a couple of break-points in the eighth game while Bhupathi-Damm had as many in the 11th but all were saved.

In the tie-breaker, Bhupathi-Damm were up a mini break early and raced to a 2-0 lead, but the Indian-Serbia combo allowed them only one more point thereafter as they seized the next five points before taking the set.

In the second set, games went with serve till Paes and Zimonjic broke in the 12^th game. That break clinched them the match after an hour and 52 minutes.

Bhupathi and Damm had caused the biggest upset of the tournament when they ousted top seeds Bob and Mike Bryan of the United States in the first round of euro 2,082,500 tournament.

Paes and Zimonjic will meet fourth seeds Michael Llodra and Fabrice Santoro, who advanced after James Blake and Andy Roddick conceded a walk-over.

In other quarter-final matches on Friday, Kevin Black and Wayne Ullyett beat Wayne Arthurs and Paul Hanley 6-4, 6-4 while Mark Knowles and Daniel Nestor accounted for David Ferrer and Fernando Verdasco 6-3, 6-1.

Earlier this month Paes got the better of his Davis Cup partner, clinching a thrilling semi-final victory in the men's doubles at the Thailand Open. Paes had combined with Paul Hanley of Australia while Bhupathi teamed with Justin Gimelstob of the United States.