BANGKOK, Sept. 26 (Xinhua) -- Unseeded Benjamin Becker ousted Spanish fifth seed Carlos Moya in the first round of the Thailand Open on Tuesday.

The early exit for Moya deprived the tournament of another name player after the top two seeds withdrew.

Becker, ranked 79th in the world, snapped a run of seven consecutive first-round defeats stretching back to Wimbledon with his 7-6 (7-5), 6-4 win over the former world number one.

The tournament suffered a tough blow earlier Tuesday when top seed and world number three Novak Djokovic withdrew with a back injury sustained during Serbia's weekend win over Australia in Davis Cup competition.

World number two Rafael Nadal had already pulled out at the weekend due to tendinitis in his left knee.

The withdrawals leaves Andy Roddick, who helped the United States book a spot in the Davis Cup final in December with a weekend semi-final win over Sweden, as the top seed here.

In other matches on Tuesday, seventh seed Ivo Karlovic of Croatia moved through to the second round with a straight-set win over Spain's Feliciano Lopez.

Germany produced a pair of wins over Americans, with Mischa Zverev beating Michael Russell 6-4, 3-6, 6-1 and Dominik Meffert putting out Amer Delic 7-5, 6-1.

Local favourite Danai Udomchoke staged a heroic comeback after four consecutive first-round defeats, overcoming Harel Levy of Israel, 5-7, 7-6 (7-4), 6-3.