Barcelona are fearful that Manchester Uniteds greater financial strength will see the Red Devils hijack their move for Chelsea winger Willian.
Barcelona submitted a third offer of around £55million for the 29-year-old on Friday and feel theyre close to their limit of what theyd pay to sign Willian.
The Brazil star is adored by Jose Mourinho and the Portuguese boss has done little to disguise the fact that hed like to sign him for Manchester United.
Chelsea hope to spark a bidding war for Willian by getting Manchester United to rival Barcelona for the Brazilians signature.
Willian is believed to be keen on moving to the Camp Nou but the Daily Mail report Barcelona fear United will hijack the deal.
The La Liga giants are yet to receive a response from Chelsea after their third bid and are unwilling to stretch much further to sign the winger.
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United, on the other hand, are desperate to sign a right winger and have cash to spend after the outfield arrivals of Fred and Diogo Dalot this summer.
Mourinho was pessimistic about the clubs chances of signing more players this summer during a press conference on Uniteds pre-season tour but the club are working hard on two more deals.