Top seed Wang Hao and second seed Timo Boll?met no challenges?in the first round of the men's singles at the World Table Tennis Championships in Rotterdam on Tuesday.

After losing the first game, Wang Hao set things straight by beating Ju Lin from the Dominican Republic 5-11, 11-5, 11-3, 11-8, 11-8. He will meet Andrej Gacina in the next round.

Wang was not feeling well from the start. "I got a slow start in my first match. I didn't feel comfortable because of the way my opponent was playing," he declared. "When he slowed down his pace, I also slowed down. I lost the first game, but then I turned the match around."

Later in the afternoon second seed Boll from Germany defeated Kenji Matsudaira from Japan also in five games: 11-8, 11-6, 11-4, 6-11, 11-4. He will play Yang Zi from Singapore in the second round

Boll was satisfied with his first performance. "It's always a little difficult," he said. "I had to get used to the new hall. In the end it was a good match. He was not an easy opponent, played very aggressive and risked a lot. It was not the easiest opponent to start with, but I am happy with my form. Of course I have to improve and get more confidence. I don't look too far ahead. Let's concentrate on my next opponent first."

Boll is still waiting for his first world title. That's not the case for Swedish giant Jorgen Persson. The world champion of 2001 had problems in his opening match against Wu Chin-Chi from Chinese Taipei 3-11, 13-11, 11-2, 12-10, 4-11, 11-3.

Despite his experience Persson admitted he was nervous. "That's why I did not get the start I wanted," he said. "Nervousness is a good sign, but maybe it was a little too much. I am happy to win this tough match. Now I feel more relaxed. At least I want to be there on Sunday. That's a tough goal, but you have to have goals."

The other Chinese players also qualified for the second round. Ma Lin (3/4) was stronger than Romanian Andrei Filimon (11-6, 11-9, 11-3, 12-10), Zhang Jike (3/4) beat Bora Vang (Turkey) 11-2, 11-4, 12-10, 11-6, Ma Long defeated Tomislav Kolarek (Croatia) 11-2, 11-5, 11-6, 11-5, Xu Xin eased past Tomas Konecny (Czech Republic) 11-6, 11-4, 11-6, 11-3, Wang Liqin beat Lubomir Pistej (Slovakia) 11-2, 11-1, 13-15, 11-9, 11-6 and Chen Qi left Daniel Habesohn (Aut) behind in four games: 11-9, 11-5, 11-8, 11-4.

Vladimir Samsonov from Belarus was able to defeat Paul Drinkhall from England in 11-7, 11-6, 11-8, 11-5.