Manchester United's move for Sporting Lisbon defender Marcos Rojo has hit a major snag amid claims that Sporting Lisbon could end up in court over a row with Doyen Sports, who own part of the full-back's economic rights.
The Red Devils are keen on bolstering their options at the back following the departures of Nemanja Vidic, Rio Ferdinand and Patrice Evra this summer.
Ajax defender Daley Blind is likely to be the first man new Manchester United boss Louis van Gaal brings into his squad, and the Dutchman has set his sights on a move for Rojo when that transfer is complete.
Reports claim that the Red Devils had tabled a £16 million bid for the young Argentinian who was looking to force a move to Old Trafford - however the complex nature of his ownership means that deal now may not happen.
Doyen own 75% of the young defender's economic rights, but Sporting have the final say over whether to accept any transfer offer. However if the Portuguese club choose not accept any bid for Rojo, which appears to be the case with Manchester United's offer - then they would be liable to pay the equivalent of 75% of the rejected offer to Doyen, which in this case would be £12 million.
20% of any fee Rojo generates over £4 million would be due to Spartak Moscow, which would leave Sporting with a tiny fraction of the £16 million offered by Manchester United if they had accepted that bid.
Instead the Portuguese side are holding out for a sizeable offer and would like the Red Devils to get near or match his £30 million release clause. So far Sporting have refused to cough up the cash for Doyen, who have now released a statement threatening them with legal action unless they hold up their end of the contract.
A statement read: "(Sporting are) making mindless demands as a condition of releasing the player.
"If Sporting want to keep Rojo they must compensate the fund under the terms and deadlines set forth by the contract. If necessary we will not hesitate to use every legal resource at our disposal to fully defend our rights and interests."
Big bid needed
Sporting have responded by cancelling their contract with Doyen - all of which points to a lengthy legal battle.
That is bad news for Manchester United, who would see their swoop for Rojo put on the back burner until his ownership is sorted out. With just three weeks of the transfer window left it is unlikely the issue can be resolved in time - unless they come up with a much-improved offer near £30 million that would make all sides happy.
Van Gaal is keen on securing Rojo in order to provide cover at centre-back and at left-back, where he was deployed during the World Cup.