Flushing Meadows, NY -- (Sports Network) - World No. 1 Ana Ivanovic survived her first-round match Tuesday at the U.S. Open.

The Serbian Ivanovic, who's battled a thumb injury in recent weeks, snuck past Russian Vera Dushevina 6-1, 4-6, 6-4 on a beautiful sunny day at this Big Apple fortnight.

Ivanovic appeared to be cruising on Day 2, up a set and leading 4-2 in the second, but some sloppy play allowed her Russian counterpart to sneak into the match.

Dushevina fought back to claim the second set and was leading 3-2 in the third before Ivanovic righted the ship. The Serbian star went on to capture the third by converting on a third match point after 2 hours, 3 minutes of uneventful tennis.

Ivanovic is the reigning French Open champ and was this year's runner-up at the Australian Open. She's played in three of the last six major finals.

The 20-year-old Ivanovic was joined in the second round by surging Russian star Dinara Safina, who handled American teenager Kristie Ahn 6-3, 6-4 on the grounds at the USTA Billie Jean King National Tennis Center. The sixth-seeded Safina was the French Open runner-up to Ivanovic and the runner-up at the Olympic tennis tournament two weeks ago.

Safina is the younger sister of the 2000 men's U.S. Open champion Marat Safin.

Ninth-seeded Agnieszka Radwanska of Poland cruised with a 6-4, 6-2 pasting of Kazakhstan's Yaroslava Shvedova, while an upset came when former Top-20 German Anna-Lena Groenefeld grounded 11th-seeded Slovakian Daniela Hantuchova 6-4, 6-2. The former Top-10 Hantuchova has now dropped eight of her last 12 matches and hasn't won back-to-back matches since March.

In other action involving Top-16 seeds, No. 13 Hungarian Agnes Szavay topped American Gail Brodsky 7-5, 6-3 and No. 16 Italian Flavia Pennetta overcame Swiss Stefanie Vogele 2-6, 6-2, 6-2 at the fourth and final major of the year.

Additional seeded victors were No. 20 Czech Nicole Vaidisova and No. 30 Japanese Ai Sugiyama, while Swiss Timea Bacsinszky upended 31st-seeded Frenchwoman Virginie Razzano 6-4, 6-1.

Other first-round winners were Frenchwoman Julie Coin, Taipei's Su-Wei Hsieh, Chinese Shuai Peng, Italians Roberta Vinci and Tathiana Garbin, Belarusian Olga Govortsova and Colombian Mariana Duque Marino.