Herrera, De Gea and Mata feel 'treated differently' to English team-mates
Ole Gunnar Solskjaer faces the first significant test of his authority as Manchester United manager after revelations that his Spanish contingent are growing disillusioned by delays to contract talks.
But the Mail On Sunday are reporting that the trio feel their English counterparts are receiving preferential treatment when it comes to negotiating terms on prolonging their stays at Old Trafford.
United have lost their last four away games in all competitions - the first time they have suffered such a run since 1999 - but it is not just matters on the pitch that are currently causing concern for the club's hierarchy, and for Solskjaer.
David De Gea is yet to sign a new contract with Manchester UnitedGetty Images
Dressing-room harmony was at an all-time high following the miraculous Champions League victory over Paris Saint-Germain in March, but United's familiar old failings have returned during a run of five defeats in seven games - and Solskjaer's attempts at restoring a feel-good factor to Carrington is being undermined by a 'home-based' strategy first deployed by Sir Alex Ferguson.
A rather damning statistic that emerged in midweek was that in Ferguson's penultimate season, United's Champions League group-stage exit confirmed by defeat in Basel in December 2011, saw no fewer than four of the current squad playing in the 3-0 defeat to Barcelona at the Camp Nou on Tuesday.
Chris Smalling, Phil Jones and Ashley Young - along with De Gea - have somewhat surprisingly survived three managerial reigns in the seven-and-a-half years since the 2-1 defeat to the Swiss club - and all three Englishmen have indeed signed new contracts this season.
Ander Herrera looks to be heading for the Old Trafford exit doorPA Sport
United are keen to promote members of their academy, and the Mail On Sunday claim that the stance on overseas players has left Paul Pogba 'with a foot in each camp' having developed as a youngster at United whilst forming strong relationships with the club's Latin players - whose representatives believe they are being treated differently.
Herrera is widely reported to be close to agreeing terms with Paris Saint-Germain after talks stalled with United, while the future of De Gea will come back into the spotlight in January, when the goalkeeper will be allowed to sign a pre-contract agreement with European clubs ahead of a free transfer in summer 2020.
Juan Mata's Manchester United expires this summerGetty Images
Alexis Sanchez remains the highest-paid player in British football history, sitting on his £26m-a-year wages, and the Chilean heads a list of senior players that United will seek to offload this summer.
Solskjaer's side are sixth in the Premier League but can go level on points with third-placed Tottenham with a win against Everton at Goodison Park later on Sunday.