Nestor and Zimonjic suffer opening defeat at finals

LONDON (Reuters) - Top seeds Daniel Nestor and Nenad Zimonjic suffered a shock defeat in the ATP World Tour Finals on Sunday when they were beaten by Poles Mariusz Fyrstenberg and Marcin Matkowski in their opening Group A round-robin match.

The Canadian-Serbian world number one pairing, this year's Wimbledon champions, went down 6-4 6-4 at the O2 Arena to damage their chances of clinching the year-end top ranking.

American Bob and Mike Bryan, who are hoping to overturn an 930-points deficit in the rankings here, begin their Group B matches on Monday against Max Mirnyi and Andy Ram.

(Reporting by Martyn Herman, editing by Pritha Sarkar)