Fraudsters are targeting young footballers across the world offering them fake trials in return for money.
Middlesbrough Football Club said it had been contacted by would-be professionals saying they had been offered trials by the club.
Club spokesman Paul Dews said in one case $150 (£116) was demanded but no cash was handed over.
A number of other clubs have been targeted and Middlesbrough has informed the Football Association (FA).
Mr Dews said the club had received at least 15 queries – from within the UK, Africa and the Caribbean – asking if the offers were genuine.
“We understand we are one of a number of clubs whose name is being used in this manner and have reported this to both the police and the FA, who we are currently assisting in their investigations,” he said.
Impersonating football agents
The FA said there had been a “number of reported scams/schemes in different areas of the country”.
Young players are promised trials and they or their family are asked for payment in advance to cover “insurance and travel”, it said.
Once the money is sent no more is heard.
The FA said it had alerted clubs and local police, and issued a warning to players and parents.
In the latest scam fraudsters had been impersonating football agents but did not appear to have received any money so far, Middlesbrough said.
Mr Dews said “any invitations for players to join on trial would always be made directly from the club and not from any third parties”.