Manchester United fear the Premiership's referees may drive Cristiano Ronaldo out of the country.
The Daily Mail says manager Sir Alex Ferguson and members of the Old Trafford hierarchy had been increasingly confident of keeping the world's best player beyond the end of this season.
But what Ferguson describes as a lack of protection for his player is becoming a major concern for the English and European champions, particularly after Ronaldo clashed with referee Phil Dowd at Craven Cottage in Fulham's surprise 2-0 victory on Saturday.
The relationship between Ronaldo and leading referees appears to have disintegrated and, while United accept that the Portugal winger is partly to blame, they argue his apparent disrespect for match officials is his response to their failure to protect him.
Ferguson says the "systematic fouling" of Ronaldo has become a popular 'tactic' in the Premier League and statistics do prove that he is fouled more than any other United player.
Now there is a real worry that the opportunity to make a summer move to Real Madrid in Spain, where referees are less tolerant of challenges, is becoming a more attractive proposition to the FIFA World Player of the Year.