OSAKA -- Top-ranked Wang Nan and Wang Liqin of China posted easy wins Thursday to advance in the singles events at the table tennis World Championships in Osaka. Olympic champion Wang Nan rolled over North Korea's Kim Hyon Hui in straight sets 21-15, 21-14, 21-19 in a fourth-round match to advance to Friday's quarterfinals in women's singles.

Wang Liqin, meanwhile, needed five sets to halt world No. 21 Lucjan Blaszczyk of Poland 21-13, 21-18, 16-21, 12-21, 21-10 in the round of 32 to advance in the men's singles event. In a match pitting former world champions, 1991 winner Jorgen Persson of Sweden prevailed in full sets over 1993 champion Jean-Philippe Gatien of France 21-12, 21-17, 19-21, 16-21, 21-19 to move on to a fourth-round meeting with Wang.

Also, all three medalists from last year's Sydney Olympics -- Kong Linghui and Liu Guoliang of China and Sweden's Jan-Ove Waldner -- posted wins to advance.