London, Jul 30 (IANS): Serbia's Novak Djokovic dropped a set in his first-round match on a historic day at the London Olympics tennis tournament at Wimbledon, where the play took place indoors for the first time in the modern Games era as the Centre Court roof was closed due to heavy rain Sunday.

Thirty matches scheduled for Sunday were postponed because of rain while four other matches were suspended and will be completed on Monday.

Djokovic, the World No.2 and flag bearer for Serbia at the Opening Ceremony Friday night, dropped the first set in his match with Fabio Fognini of Italy but went on to win 6-7(7), 6-2, 6-2. The two players had met twice before, on clay and hard courts, and both times Djokovic won in straights sets.

The Serb had won a bronze in the 2008 Beijing Olympics.

Frenchman Jo-Wilfried Tsonga, the fifth seed and Wimbledon semi-finalist, also dropped the first set in his match against Tomasz Bellucci from Brazil, but eventually won 6-7(5), 6-4, 6-4 in what was their first encounter on any surface.

Australian No.1 Bernard Tomic was defeated by 15th seed Kei Nishikori of Japan 7-6(4), 7-6(4). Tomic had four set points in the first set that he failed to convert and this defeat brought his losing streak to seven matches.

Andy Murray started his campaign to become the first Briton to win an Olympic medal since Tim Henman and Neil Broad, who won silver in the men's doubles at Atlanta 1996. He took just 89 minutes to defeat Stanislas Wawrinka of Switzeland 6-3, 6-3. This brought Murray's winning record against the Swiss to seven out of 11 meetings on three surfaces.

In the women's singles, Agnieszka Radwanska of Poland, the World No.2 and second seed, lost her first-round match to 24th-ranked Julia Goerges from Germany.

Radwanska, who was runner-up to American Serena Williams at this year's Wimbledon and was Poland's flag bearer at the Opening Ceremony, was broken in her first service game and lost the first set. She came back to take the second set on a tiebreak, but eventually lost 7-5, 6-7(5), 6-4.

The Radwanska-Goerges match was the first on the Centre Court and for more than two hours was the only tennis being played at Wimbledon as play on the outside courts was suspended due to heavy rain. It marked a historic moment, as it was the first tennis match at an Olympics in the modern era to be played under cover after the court roof was closed.

Russia's third seed Maria Sharapova raced to a 65-minute win over Shahar Peer from Israel at 6-2, 6-0. Sharapova has now defeated the Israeli in each of their seven meetings on three surfaces.