Nadal, Djokovic claims World Finals wins

LONDON, Nov. 22 (UPI) -- World No. 1 Rafael Nadal rallied for a tough three-set victory in joining Novak Djokovic as round-robin winners Monday at the ATP World Tour Finals in London.

Nadal rallied from being a set and a break down for a 3-6, 7-6 (7-5), 6-4 win over eighth-seeded Andy Roddick in Group A play. Djokovic, the No. 3 seed, opened the group's round-robin with a 6-3, 6-3 sweep of sixth-seeded Tomas Berdych.

Nadal was far-from sharp in the early going, committing two double faults in dropping serve in the match's second game. Roddick made that break stand for the set and was up a break early in the second before Nadal rallied.

Roddick had one other good opportunity, winning two points off Nadal's serve to go up 5-3 in the tie-breaker but Nadal answered with a mini-break of his own to take control.

Djokovic didn't face a break point in his match. He won a healthy 72 percent of the points on serve in beating the sixth-seeded Berdych. He was able to cash in three of seven break points he forced on Berdych, including one in the opening game of the match.

Djokovic also broke Berdych's serve in the second game of the second set to establish control of the match.

No. 2-seeded Roger Federer and fifth-seeded Andy Murray, who claimed first-day wins Sunday, meet in Tuesday's first match while Robin Soderling and David Ferrer square off in the Group B night match.

The top two players in each group advance to the tournament semifinals Saturday.