West Ham manager Alan Pardew believes there is a gambling culture among his players which he is determined to 'police'.
Goalkeeper Roy Carroll was reported this week to have sought treatment for alcohol and gambling troubles, something denied by Carroll's father, who insists his son is suffering from 'stress'.
However Pardew said in the News of the World: 'I am going to address the situation with gambling, because it is not the first time it has happened at the club.
'What has come out of Roy's problem is that there is gambling going on within the group and I have to sort it out before it becomes a bigger issue.
'It is a difficult situation for a manager to police because it is not as if you see piles of money change hands.'
Former Manchester United goalkeeper Carroll, 29, has not played for the Hammers first team since October 14 but is expected to return to training soon.
Pardew claims poker is the most popular game among footballers, and fears big sums are being gambled on cards, to the detriment of team spirit.
He added: 'I think the problem is getting bigger in football because poker has become enormously popular and players in the top wage bracket can bet at a different, higher, level.'