ROME: Concerns over the match-fix gambling probe involving fourth seed Nikolay Davydenko haunt the US Open on the eve of the Grand Slam event.

The 26-year-old Russian, a semi-finalist here 12 months ago, will begin the year’s final Grand Slam event here Monday against US wild card Jesse Levine still dogged by a second round withdrawal earlier this month.

The internet betting site Betfair refused to pay out on Davydenko’s loss in an ATP event at Sopot, Poland, in which Argentina’s Martin Vassallo Arguello won 2-6 6-3 2-1 when the Russian retired with a foot injury.

Seven mn dollars in wagers, 10 times more than normal for such a match, swung to Arguello even after Davydenko won the first set. That irregularity touched off a probe into the matter.

“It’s disappointing,” US fifth seed Andy Roddick said. “You don’t want to hear about it. You don’t want tennis’ storylines to be that. I’m happy that at least they are putting forth the effort to investigate it, take care of it and try to make sure it’s an isolated incident.”

With the National Basketball Association facing a similar problem after a referee was linked to gamblers last month, Roddick knows the impact a broader scandal could have upon his sport. “I’m pretty confident it’s an isolated event,” he said. “Until we know something, until due process takes its course, you can’t really say anything.”

A notice posted by the US Tennis Association at the US Open vowed punishment for anyone providing aid to gamblers. “The participation in or aiding and abetting, directly or indirectly, with any form of gambling or betting involving tennis is strictly prohibited,” the posting read. “The USTA has a zero-tolerance policy on gambling or betting involving tennis and any violation of such policy will result in immediate disciplinary action.”

Russia’s top-ranked woman, second seed Maria Sharapova, said the turmoil surrounding her homeland’s top-rated man has not aroused any concerns on the WTA circuit. “It doesn’t seem like the WTA Tour has any issues with it,” Sharapova said.