Olympic [Images] champion Elena Dementieva struggled to a 6-4, 7-5 victory over Akgul Amanmuradova of Uzbekistan in the first round of the U.S. Open on Monday.

The Russian fifth seed saved two set points in the second set before clinching victory in one hour, 28 minutes to set up a second-round match against Pauline Parmentier of France [Images].

Dementieva, the runner-up in 2004, was made to fight all the way by world number 78 Amanmuradova, but one break gave her the first set.

Amanmuradova led 5-3 in the second and had two set points in the 10th game, but Dementieva saved them both.

Former champion Svetlana Kuznetsova [Images] also made a confident start to her campaign with a 6-4, 6-2 win over Zhang Shuai of China.

The Russian third seed, the runner-up last year, won a tight first set and then eased through the second to claim victory in one hour 17 minutes.

World number 243 Zhang, playing her first grand-slam match, matched Kuznetsova early and had a break point to level at 5-5 in the first set.

But Kuznetsova held on to take the set and an early break in the second put her on course for a place in the second round against Czech Lucie Safarova or Romania's Sorana Cirstea.

Lindsay Davenport [Images] enjoyed a brisk workout on her return from a two-month injury layoff with a 6-4, 6-2 win over Canada's [Images] Aleksandra Wozniak.

The 1998 champion did not show any ill effects from the right knee injury that has kept her on the sidelines since Wimbledon [Images] and frustrated Wozniak with her heavy groundstrokes.

The American's only hiccup came when she was serving for victory. After fluffing four match points, she finally booked her place in round two with a low forehand volley.

Davenport will next meet either Russia's [Images] Alisa Kleybanova or Carla Suarez Navarro of Spain.

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