Berdych used three service breaks in topping Roddick 7-5, 6-3 and improved to 1-1 in Group A play. Roddick, seeded eighth, fell to 0-2.

Top-seeded Rafael Nadal and No. 3 Novak Djokovic, both 1-0, were to meet later Wednesday in their round-robin match.

Roddick dropped a tough match to Nadal Monday after being up a set and a break. But he didn't manage to get an advantage over Berdych, who saved both break-point situations he faced.

Both of those came in the 10th game of the first set when Berdych rallied with four consecutive points to win the game and then Berdych took the 11th game by converting his first break-point chance of the match. He didn't face a break point in the second set and finished off the victory with his third break of the day.

Group B round-robin play wraps up Thursday with No. 2-seeded Roger Federer (2-0) going against fourth-seeded Robin Soderling (1-1) and fifth-seeded Andy Murray (1-1) playing No. 7 David Ferrer (0-2).

The top two finishers in each group advance to Saturday's tournament semifinals.

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