LONDON (AP)—Austria’s Daniel Koellerer became the first tennis player Tuesday to be banned for life for attempting to fix matches.

Koellerer, a former Davis Cup player who once reached No. 55 in the world rankings, was found guilty of three violations of the sport’s anti-corruption rules, including “contriving or attempting to contrive the outcome of an event.”

The violations occurred between October 2009 and July 2010.

The Tennis Integrity Unit, an anti-corruption group, launched an investigation on behalf of the International Tennis Federation and the ATP and WTA tours. It would not specify which matches Koellerer was found to have manipulated.

Koellerer, who was also fined $100,000, denied the charges and is considering whether to appeal.

“This is a giant shock … I have been charged with approaching other players to fix matches,” he told Austrian radio station ORF Oe3. “I have been accused of asking other players to lose their match. That’s total nonsense.”

Koellerer’s manager, Manfred Nareyka, told ORF that the player “has been found guilty of fixing two matches involving other players and one match of his own,” but declined to reveal further details.

The Austrian tennis federation said it hadn’t received any official confirmation regarding the sanctions imposed on the player, who is currently ranked No. 385.

“If the sanctions … become legal, the federation will take appropriate measures on national level,” the Austrian body said.

Koellerer, nicknamed “Crazy Dani,” turned professional in 2002 but soon courted controversy by being suspended by the ATP twice for bad behavior on court—in 2004 and ’06. On the second occasion, he was banned for six months.

In August 2010, Koellerer and Nareyka were placed on two years’ probation after the player’s personal website listed odds for matches and had links to sites for placing bets. At that time, Koellerer and Nareyka admitted breaking rules about “facilitating betting.”

The tennis anti-corruption group said Tuesday the latest findings came following a separate investigation.

Koellerer climbed to a career-best No. 55 after reaching the third round at the 2009 U.S. Open and won six titles on the lower-ranked Challenger circuit. He never won an ATP Tour event.

Koellerer played Davis Cup for Austria once but lost both his singles matches during the team’s 3-2 win over Slovakia in 2010.

Tuesday’s findings were considered at an independent anti-corruption hearing in London on April 27-28, the details of which will not be released.

Russian player Nikolay Davydenko was cleared in 2008 of any wrongdoing following an investigation by the ATP into suspicious betting patterns surrounding his match against 87th-ranked Martin Vassallo Arguello the previous year.

Among the lower-ranked players sanctioned by the ATP in recent years for betting on matches were five Italians—Potito Starace, Daniele Bracciali, Alessio Di Mauro, Giorgio Galimberti and Federico Luzzi—who were given suspensions ranging from six weeks to nine months between 2007-08. Late French player Mathieu Montcourt was also banned for two months in 2008.