MELBOURNE, Australia -- Russian tennis star Nikolay Davydenko is once again embroiled in a dispute with ATP investigators over phone records and, once again, a major championship provides the competitive backdrop for the legal standoff.
More than five months after Davydenko's involvement in a tennis match that led to a worldwide betting scandal, ATP investigators are now seeking phone records from Davydenko's wife, Irina, and his brother, Eduard, and have set a deadline of 15 business days after Davydenko's last match at next week's Australian Open, his attorney, Frank Immenga, said when reached at his office in Frankfurt, Germany.
"It makes me angry because it takes so long,'' Davydenko told the BBC on Friday in Melbourne, where he is playing in a warm-up tournament for next week's Australian Open. "I can't understand what they want from me. I have given them everything, all the information. When will this end? I do not have any trust in the ATP.''
The ATP's most recent deadline for turning over evidence is more forgiving than the one Davydenko faced last August when the ATP formally requested his personal phone records on the third day of the U.S. Open and demanded the request be met within seven business days.
Davydenko, No. 4 in the world, has been under scrutiny since Aug. 2, when he played a match in Sopot, Poland, against Argentinean Martin Vassallo Arguello, then ranked No. 87.
According to the London-based gambling Web site Betfair, Davydenko was a slight underdog to Vassallo Arguello before the match began, despite the substantial difference in rankings, and an even greater underdog, oddly, after he won the first set.
"We've got forty- to fifty-thousand pairs of eyes on the site at any given time and everybody was saying there's something wrong here," said Mark Davies, Betfair's managing director, recalling the feedback the Web site received from bettors during the match.
At one point during the match Davydenko, the defending tournament champion, soared to an 11-1 long shot on Betfair, despite the fact he was facing a player who'd never won an ATP singles title.
Davydenko withdrew from the match in Sopot after trailing Vassallo Arguello 2-6, 6-3, 2-1, later blaming a stress fracture in his left foot for his early exit.
Concerns about suspicious betting patterns led Betfair to make the unprecedented decision to void more than $7 million in bets.
"We said, 'Look, the betting doesn't appear to be fair,'" Davies said. "That is a very, very long way from saying that we think that something is inherently corrupt in either of the players or in the match."
Two days after the match in Poland the ATP launched a formal investigation into suspicious gambling activity.
"We never at any point mentioned Davydenko and went to great lengths in fact to stress that nobody should mention any player because their reputations were at stake," said Etienne de Villiers, ATP executive chairman.
In recent months the ATP has tried to strike the delicate balance of investigating suspicious gambling around the Sopot match without unfairly indicting one of the sport's premier players.
"The minute something that happens on a tennis court has a doubt as to whether that match occurred by virtue of some corruptible influence, you're done."
On Aug. 29, while Davydenko was in New York for the U.S. Open, Gayle Bradshaw, the ATP's vice president for rules and competition, requested records for all phones used or registered to Davydenko and ordered the records turned over within seven business days.
After appealing that request to an ATP hearing officer, Davydenko eventually agreed to turn over his personal phone records in early December, Immenga said.
What's different about this latest request, according to Immenga, is that the ATP code, which all players sign, does not require them to provide phone records from third parties.
"Nikolay signed the ATP code," Immenga said. "His wife and his brother, they didn't sign anything, therefore I question whether they have jurisdiction."
But according to the ATP code, players suspected of corruption, or their support personnel and their family members, can be required to turn over telephone records, Internet service records, computers and hard drives within seven business days of a written request.
"The continued delays experienced in receiving key information requested from the player, and his associates, is naturally contributing to the ongoing length of the investigation," said Kris Dent, an ATP spokesperson.
Still, Davydenko sounds determined to dig in for a fight on this latest request from the ATP.
"I provided telephone connection data at the beginning of December and then the ATP wanted data from my wife and brother, which we refused," Davydenko said earlier this month at the Qatar Open in Doha.
"If we allowed that to happen, they would be taking data from my grandmother," Davydenko said.
He went on to call the ATP probe into the Sopot match "idiotic."
While Davydenko and his attorney rail at the lengthy ATP investigation, it is clear their resistance to turning over key evidence has prolonged the effort.
If Davydenko decides to appeal this latest request for phone records before an ATP hearing officer, it will further delay an investigation that has made him the subject of unwelcome scrutiny and, arguably, the poster boy for tennis' match-fixing scandal.
"I want them to know that I am not guilty in this matter," Davydenko recently told ESPN through an interpreter, when asked about the negative perceptions of tennis fans. "I am clean and in future tournaments they will see me as a tennis player and not as a person who would lose a match on account of wagers."
In addition to seeking phone records, ATP investigators have interviewed Davydenko, his wife, brother and Vassallo Arguello, the man he faced on the red clay of Sopot.
"I don't think the investigation is going to show that Davydenko was involved in anything," Vassallo Arguello recently told ESPN. "I was on the court with him, and everything that happened on the court seemed very normal to me."
Several sources have told ESPN that the ATP investigators are concerned less about the volume of betting on the obscure match in Poland than with the concentration of the money wagered on Vassallo Arguello to win.
According to Immenga, ATP investigators told him in early November that nine Betfair account holders based in Russia stood to make more than $1.5 million if Davydenko lost to Vassallo Arguello.
"We could see too much concentration of the betting in question," said Betfair's Davies, "so we said 'look, we're just not comfortable with this,' and we stopped the bets."
Since 2003, Betfair has had a memorandum of understanding with the ATP, which allows the company to provide confidential account information when suspicious betting activity occurs.
That working relationship between the governing body of men's tennis and a gambling Web site has led some to question whether it's an unholy alliance.
Betfair has long maintained that its ability to provide an audit trail for wagering on any sport helps it serve as watchdog for corruption.
"The reality is that the way to prevent problems is to make sure that all the betting is transparent," Davies said.
"Our lives would be a lot simpler if we didn't have gambling, no question," de Villiers concedes. "But it's a reality and I'm very relieved that people like Betfair take their responsibility very seriously."
For his part, Davydenko denies any connection to anyone who wagered on the match.
When asked to explain the suspect betting pattern, he points to his foot injury.
"I do have evidence that I was injured," Davydenko said. "That's why I couldn't finish the match."
Davydenko says he told only his wife and an ATP trainer about the injury before the match and that it's possible somebody found out and used that inside information to bet against him.
Immenga even has gone so far as to question whether ATP physiotherapist Christiaan Swier, who treated Davydenko before and at several points during the match, somehow tipped gamblers to Davydenko's injury.
When contacted by ESPN, Swier denied doing any such thing.
"I didn't talk to anybody," Swier said. "There's nobody who came up to me and said: 'Is he injured or not?' But I don't know. The training room is not a closed environment."
Swier acknowledged that he, too, has spoken with ATP investigators but he referred all other questions to an ATP spokesperson.
Swier's denial speaks to one of the larger issues being examined within the sport of tennis.
Limiting access to players prior to matches is just one of the many anti-corruption measures being considered by tennis' four governing bodies.
"If Sopot did one good thing, it galvanized the industry, the tennis industry, to say, 'OK, let's really get onto this. Let's really ensure that we do remain ahead of this threat,'" de Villiers said.
Since August, several players, including Davydenko's Russian Davis Cup teammate, Dmitry Tursunov, have gone public with stories of people offering money to throw matches.
Tursunov told ESPN that on two separate occasions he's received anonymous phone calls to his hotel room before matches, the first time at an event in Madrid in the fall of 2006, the second at an event in Indian Wells, Calif., last March.
In November, the ATP passed a rule requiring players to report such encounters within 48 hours but even that, admits de Villiers, may not be enough to eliminate the threat of corruption.
"At the end of the day we cannot stop access, corruptible access to a player," de Villiers said.
That hasn't stopped Tennis Australia, the organization that runs the Australian Open, from trying.
Soon after the U.S. Open, Tennis Australia announced that betting windows, a fixture on the Melbourne grounds during the tournament, would be banned.
Last month the organization took the added steps of banning the unauthorized use of laptops courtside and blocking access to gambling Web sites on publicly accessible computers at the Open.
According to de Villiers, a single integrity unit, responsible for combating corruption for all four of tennis' governing bodies, could be in place as early as March.
But the lingering question in tennis centers on the outcome of the investigation of the now infamous match last August in Poland.
"We will mount, irrespective of cost and resource, the fullest investigation to try and understand what went on and try and find the guilty party, if in fact guilt needs to be assessed," de Villiers said.
At the same time de Villiers admits that even an exhaustive investigation may yield few answers.
"We may never know," de Villiers said. "We may get to the point where we think we know but we can't prove it. We may get there."
John Barr is a reporter for ESPN's "Outside the Lines." OTL producer Willie Weinbaum contributed to this report. This report also includes information from the Associated Press.