Dubai, UAE  - Serena Williams eased through in her first match since withdrawing from a Paris semi-final, overcoming a slow start to get past Sara Errani 4-6, 6-2, 6-0 at the Barclays Championships on Tuesday.

The world number one Australian Open champion had withdrawn in France due to knee pain but showed little sign of discomfort against Errani for a place in the third round.

Williams needed to kick into gear after losing the opening set, storming in the second but double-faulting away two set points in the seventh game.

The top seed broke a game later to claim it and was untroubled in the third to wrap up the win.

World number two Dinara Safina wrote off a 6-4, 6-2 defeat as a "bad day."

Victory by Virginie Razzano of France marked the second straight loss for Safina, who also lost to Williams in the Melbourne final.

"It was not my day, I just couldn't play my game, I wasn't there." said Safina, who had won three of four matches against Razzano. "I played worse in this loss than I did in Melbourne.

"Today was one of my worst days, now all I can do is forget and get ready for Indian Wells (next month). When it's not your day, nothing you do matters."

Third seed Jelena Jankovic had better luck, getting on and off court easily over unconventional Romanian Monica Niculescu 6-3, 6-2.

The Serb, a finalist in 2005, needed a fast adjustment from indoor play in wintery Paris to the mid-20s Celsius of the Gulf.

Niculesco, ranked 48th, strikes the ball double-fisted off both wings in a style similar to that of Frenchman Fabrice Santoro.

"She's an unusual player with a lot of slice and drop shots. You always have to expect anything.

"I was so glad to win in two sets and get off the court as soon as possible."

Jankovic lost the number one ranking at the Australian Open as Williams took over the top spot.

Fifth seed Vera Zvonareva won a Russian clash over Vera Dushevina 6-0, 6-3 while number six Venus Williams crushed Russian Anastasia Pavlyuchenkova 6-0, 6-1

Two French seeds advanced to the third round, with Alize Cornet beating German Julia Schruff 6-1, 6-2 and Marion Bartoli defeating Italy's Francesca Schiavone 7-6 (7-5),
3-6, 6-3.

The tournament continues to be rocked by fallout from the banning of Israeli Shahar Peer by the government, which denied her a visa and provoked a firestorm of controversy.

Reports are circulating that the future of the event on the WTA is in serious doubt. The ATP may face a similar situation next week at the event if Israeli doubles player Andy Ram is also denied entry into the UAE. dpa