Locker rooms thieves are targeting the world's top tennis players and Wimbledon is the latest victim.
Players and coaches on the international circuit have suffered at least 15 thefts this year from Melbourne to Paris, sparking fears that an insider could be responsible.
The first to be hit at Wimbledon this week were former French Open champion Albert Costa who had a bag of euros and dollars stolen and French player Michael Llodra, who had his wallet taken.
"We will try to do everything we can to ensure this doesn't happen again on our premises," a Wimbledon spokesman said after the robberies were reported.
Despite strict checks on who comes into the locker room on the tour, these are just the latest in a rash of incidents that have alarmed the governing body of men's tennis.
Asked if insiders might be to blame, ATP (Association of Tennis Professionals) spokesman Andre Silva said: "We obviously don't know who is doing it and I don't want to speculate."
Silva estimated that there had been 15 thefts already this year.
Czech player Radek Stepanek, the fiance of Switzerland's former world number one Martina Hingis, had 5,000 euros ($6,723) taken in Monte Carlo.
Sweden's Jonas Bjorkman, reported the loss of personal effects at both the Australian and French Open tournaments.
Frenchman Sebastian Grosjean was one of three players robbed at the Queen's grasscourt tournament in London earlier this month.
ATP spokesman Silva said: "We do take it seriously. Last year we passed a rule tightening up credentials in the locker room. Players have to tell us who their coaches are.
"We want this to be resolved but we need the players to work with us in a combined effort. The players' council will be involved in any new decision as this involves what we feel is a very private area for them."