Venus rolls; Stephens exits Doha

Doha, Qatar ( - Former world No. 1 star Venus Williams was an easy winner, while her 14th-seeded fellow American Sloane Stephens came up a first-round loser Monday at the $2.44 million Qatar Open.

The unseeded Williams waltzed past Croatian qualifier Petra Martic 6-2, 6-2 on the hardcourts at Khalifa International Tennis Complex.

Stephens. meanwhile, gave way to Czech qualifier Petra Cetkovska 7-5, 6-1, and another upset cane when Bulgarian qualifier Tsvetana Pironkova tripped up 11th-seeded Italian Roberta Vinci 6-3, 6-3.

Also on Day 1, Chinese Peng Shuai topped Russian qualifier Nadia Petrova 7-6 (7-5), 7-5, Annika Beck bested fellow German Mona Barthel 7-6 (7-5), 6-2, and qualifier Su-Wei Hsieh of Chinese Taipei doused Italian Flavia Pennetta 7-5, 6-3. Petrova titled here back in 2006.

The first round is scheduled to conclude with several matches on Tuesday, including ones for former world No. 1 Ana Ivanovic, Australian Open runner-up Dominika Cibulkova and former U.S. Open champ and 2012 Doha runner-up Sam Stosur.

This week's top seeds are Aussie Open champion Li Na, former Wimbledon runner- up Agnieszka Radwanska and former Wimbledon champ Petra Kvitova, who will battle the 33-year-old Williams in the round of 32 on Wednesday.

Two-time champion Victoria Azarenka is not defending her titles this week. She beat Serena Williams in last year's marquee Doha finale.