NEW YORK - The head of the men's professional tour promised on Saturday to use "all means available" to protect tennis' appeal and integrity after a betting scandal.

NEW YORK - The head of the men's professional tour promised on Saturday to use "all means available" to protect tennis' appeal and integrity after a betting scandal.

There will be an investigation into suspicious betting on a match involving No 4-ranked Nikolay Davydenko.

Etienne de Villiers, the ATP's executive chairman, said in an e-mail to The Associated Press that "independent, external resources" would be used to look into why a British online gambling company received about $7 million in wagers on the match, 10 times the usual amount.

Most of the money was on No 87 Martin Vassallo Arguello of Argentina to win - and some of those bets were placed after he lost the first set to Davydenko. The gambling company, Betfair, voided all bets on the second-round match on clay at Sopot, Poland. Davydenko won the second set then retired injured in the third. - Sapa-AP