The covers are pulled off Centre Court after the roof was closed at the Wimbledon tennis championships in London June 20, 2011. [Photo/Agencies]

LONDON - Relentless rain troubled the first competition day of the Wimbledon Championships on Monday, resulting in 29 matches being cancelled or suspended.

It's sunny when the 125th grass-court Grand Slam unveiled at noon with five-time champion Venus Williams comfortably winning over Akgul Amanmuradova from Uzbekistan 6-3, 6-1 in the women's first round before men's singles defending champion Rafael Nadal blast past American Michael Russell.

Nadal, 25, began his title defending campaign with a comfortable victory over Russell. The Spaniard only took one hour and 58 minutes to beat the world No 90 6-4, 6-2, 6-2.

Nadal will meet Ryan Sweeting from the United States in the second round as the Wimbledon debutant came from two sets down to edge out higher-ranked Pablo Andujar of Spain 3-6, 4-6, 6-1, 7-6(1) and 6-1.

Five hours later, all players on court had to retreat to the locker room while rain suddenly came and only Italian Francesca Schiavone and Aussie Jelena Dokic managed to come back to complete their match under the roof in the center court.

The sixth seed Schiavone defeated Dokic 6-4, 1-6, 6-3 before Andy Murray played the last match under the roof with a 4-6, 6-3, 6-0 and 6-0 win over Spaniard Daniel Gimeno-Traver.

"It's like almost too perfect, you know. There's no wind, obviously no sun, no sort of elements to contend with. It's different, different grass court tennis," said the world No 4 Murray, who is expected to clinch his first Grand Slam title at home soil.

The ninth seed Gael Monfils of France, the 14th seed Stanislas Wawrinka from Switzerland and Spanish Feliciano Lopez all advanced into the men's singles second round in straight sets.

In the women's singles, the second seed Vera Zvonareva of Russia needed to fight in the deciding set before seeing off American Alison Riske 6-0, 3-6 and 6-3.

Two-time Grand Slam champion Svetlana Kuznetsova came from one set down to defeat Chinese player Zhang Shuai 3-6, 6-3, 6-4.