Ruled unfit by her father Richard, former would number one Serena Williams [Images] advanced to the quarter-finals of the WTA Tier II Bangalore Open on Wednesday night because of sheer quality.

Playing well below her hundred per cent, the younger Williams phenom still proved an insurmountable task for veteran Israeli Tzipora Obziler.

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The third seeded American, playing her first match since her quarter-final loss to Jelena Jankovic at the Australian Open this year, overcame a sluggish start to beat Obziler 7-5, 6-0 in the second round. She received a bye in the first round of the tournament.

"I am just happy to be here after what I've been through in the past two-and-a-half weeks. I am definitely not feeling my hundred per cent, but I am here to play well and working on getting my body right," said Serena after the victory.

Williams started out cold, serving two double-faults in the first game. One of the favourites in the tournament, the American struggled to get off the mark and was error-prone, especially on the forehand. But, luckily for her, even the usually tenacious Obziler was off-colour and failed to take her opportunities early in the match.

Both players failed to hold serve in the first four games of the set. Williams stopped the trend when she sealed the fifth game, the first off her own serve, with a sizzling backhand cross court. The American, playing on the fast bouncy surface at the KSLTA for the first time, played well under her ability and still managed to squeeze out the first set after a decisive break in the 12th game.

"She didn't give a lot of pace to work with but she was also not very consistent. She would hit the ball flat and then hit one soft so I could not get into any kind of rhythm," said Serena, talking about her opponent's game.

Obziler, who tried to stay with the multiple Grand Slam winner for most of the first set, could not keep pace with Williams in the second. She wilted under the barrage of hard-hitting balls, and every time Williams swerved to get ready for a backhand the point was a foregone conclusion.

The American took all the three break-point opportunities she got to swing the set her way while blanking the 117-ranked Obziler.

Serena changed her racquet towards the end of the first set.

"The strings had become very lose, I think because of the temperatures here. But once I got a tighter racquet I was definitely hitting the balls better and a lot consistently. The ball was flying all over in the first set but not so much in the second," she said.

Earlier in the day, big-built Uzbek Akgul Amanmuradova upset fifth seed Agnes Szavay while Russia's [Images] Anastasia Rodionova eliminated sixth seed Sybille Bammer in the second round.

Amanmuradova continued her impressive run at the tournament as she beat Hungarian Szavay 4-6, 7-6, 6-4 two days after she had taken out defending champion Yaroslava Shvedova in the first round.

Rodionova scored a more comfortable 7-6, 6-2 win over Austrian Bammer and will play Serena in the quarter-finals.

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