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German tennis player Philipp Kohlschreiber, accused of match-fixing by an ATP source in German newspaper Die Welt, insists he has "nothing to hide" and "only plays to win".
The newspaper's source claims about 30 players are involved in match-fixing for internet betting sites, including Russians, Italians and Argentinians but also Germans, citing Kohlschreiber as "the worst".
It said two recent matches in which Kohlschreiber played were the subject of an abnormal volume of bets.