BRISBANE: Justine Henin overcame some service problems to reach the quarter-finals in her comeback tournament with a 6-4, 6-3 win over Sesil Karatantcheva today.

Henin dropped opening service game and had to defend early against powerful groundstrokes from Kazakhstan qualifier before taking control in the eighth game. She dropped serve to start the second set and was only a point from falling behind 3-0 before she rallied to win five straight games for a 5-2 lead.

The seven-time Grand Slam champion was serving for the match when she was broken for the third time. But she broke back immediately, finishing with a forehand winner to advance to a meeting with seventh-seeded Melinda Czink. Henin attributed the shaky start to the humidity and her first night match in a long time. Henin beat second-seeded Nadia Petrova on Monday in her first match since May 2008, when she retired while holding the No 1 ranking.

The 27-year-old Henin announced her comeback in September, soon after fellow Belgian Kim Clijsters won the US Open only three tournaments into a comeback from retirement. The Belgians could meet in the Brisbane final in what would serve as an intriguing buildup to the Australian Open, which starts January 18 in Melbourne.

Clijsters will play a quarter-final against Czech player Lucie Safarova, who had a 6-3, 6-1 win over sixth-seeded Aleksandra Wozniak of Canada on Wednesday. Fourth-seeded Daniela Hantuchova of Slovakia beat Hungary's Agnes Szavay 6-3, 6-1. Anastasia Pavlyuchenkova of Russia will meet third-seeded Ana Ivanovic in the quarter-finals after ousting Italy's Roberta Vinci 1-6, 6-4, 6-1.

On the men's side, top-seeded Andy Roddick got on top in a serving duel to beat Carsten Ball 7-6 (0), 6-3 and set up a quarter-final against Frenchman Richard Gasquet. Defending champion Radek Stepanek beat Ukraine qualifier Oleksandr Dolgopolov Jr 5-7, 7-6 (4), 6-2. The second-seeded Stepanek next faces American Wayne Odesnik, a 6-7 (8), 6-2, 6-1 winner over Colombia's Alejandro Falla.

Third-seeded Gael Monfils had a 6-7 (5), 7-6 (5), 6-1 win over fellow Frenchman Florent Serra and will next play veteran American James Blake, who recovered from a break down in the third set and fended off three match points in the tiebreaker to edge Frenchman Marc Gicquel 6-3, 3-6, 7-6 (6).

Roddick broke in the eighth game of the second set -- the only service break in the match -- and clinched it next game over the 22-year-old Ball, a big-serving left hander who was born and raised in California but plays for Australia. The former No 1 Roddick faced only one break point, when serving to stay in the first set, then dominated from the tiebreaker. Roddick is playing his first tournament since withdrawing at Shanghai in October with an injured left knee.