Doncaster captain Shaun Leaf has been suspended with immediate effect pending the outcome of an investigation into an allegation that he bet on his side to lose a Challenge Cup match.
The Rugby Football League have provisionally suspended the 27-year-old centre following an alleged breach of their operational rules and the sport's betting code of conduct.
The RFL today launched an investigation into a newspaper claim that Leaf gambled on his team losing the fourth-round tie against their Super League opponents by more than 38 points.
The Wildcats scored an interception try in the last minute of the match at the Keepmoat Stadium to win 50-10. Leaf missed the match with a thumb injury.
The RFL say they are also looking into an alleged breach of rules surrounding a Co-operative Championship fixture in 2009.
"The RFL will be making no further comment on these cases until the conclusion of the investigations," said a spokesman.
In 2004, St Helens duo Sean Long and Martin Gleeson were each fined £7,500 and handed three-month and four-month suspensions respectively for betting on their under-strength team to lose by more than eight points in a Super League match at Bradford.
Doncaster chief executive Carl Hall, who is also the club's main shareholder, was unavailable for comment but chairman John Scarrow confirmed an internal inquiry has been launched.
"The club consider this a serious matter," he said. "We will be thoroughly investigating it in a proper and timely manner."