BUDAPEST, April 23 (Xinhua)-- China's Olympic champion Ma Long took a belated revenge over an old enemy of his mentor Liu Guoliang, beating Aleksandar Karakasevic in straight sets at the world table tennis championships on Monday.
The 43-year-old Serbian, who eliminated 1996 Olympic champion Liu in the 1997 worlds, wilted under the barrages from defending champion Ma.
Liu, a former China head coach elected as the president of the Chinese table tennis association late last year, is overseeing China's bid to clean-sweep gold medals here.
Karakasevic collected only 19 points in his 11-6, 11-4, 11-6, 11-3 loss to Ma, who is seeking his third straight singles title at the world championships.
Chinese Liang Jingkun crushed Thailand's Supanut Wisutmaythangkoon 11-4, 11-8, 11-1, 11-3 to join Ma Long in the second round.
Top-seeded Chinese Fan Zhendong advanced at the expense of Frane Kojic, beating the Croatian 11-6, 11-5, 11-6, 12-10, while China's Xu Xin defeated Slovenia's Jan Zibrat 4-1.
German star Timo Boll had some trouble against Croatian Andrej Gacina, winning in a score of 4-2.
Boll's teammate Dimitrij Ovtcharov and Belarussian veteran Vladimir Samsonov both advanced with straight-set wins.