Marcos Rojo's move to Manchester United yet to be signed off by Premier League

• Transfer waiting to be approved, in part because of Sporting Lisbon's association with Doyen 
• The funding group are claiming 75 per cent of the £16m transfer fee
• Delay would need to be resolved by 12pm on Friday if Rojo is to face Burnley
• Rojo is yet to play for Louis van Gaal since he arrived at Old Trafford  

Louis van Gaal’s defensive concerns could deepen after it emerged that the Premier League are yet to sign off on Marcos Rojo’s transfer, partly because of Sporting Lisbon’s involvement with funding group Doyen.

Rojo moved to United for £16million eight days ago but has not yet played for Van Gaal. It had been thought that obtaining a work permit was the only delay in his registration being ratified but Sportsmail understands that the Premier League are still processing the paperwork associated with Doyen’s claim to 75 per cent of the transfer fee.

The delay would need to be overcome by 12pm on Friday if Rojo is to be eligible for the important encounter with Burnley at Turf Moor on Saturday afternoon. It is uncertain whether that will prove the case.

When Rojo was bought by Sporting from Spartak Moscow for £3.5m in 2012 Doyen are understood to have loaned the Portuguese club most of the money. 

In return the investment fund would receive 75 per cent of any future transfer fee or be repaid in full at a set interest rate – as with a lending bank. But a row between Sporting’s new president Bruno de Carvalho and Doyen broke out when he discovered the arrangement and claimed the club were being put under pressure to sell Rojo to United.

Doyen insisted this was never the case but in the end the Argentina international did switch to Old Trafford. Sporting received £8m immediately, with two further instalments of £4m due but Sportsmail understands Doyen have yet to receive a single penny and are considering legal action that could end up in court. 

United are not implicated in this in any shape and Doyen’s only concern is holding Sporting to the contract the club signed in 2012.

That wrangle in itself is not holding up the Premier League’s legal team but any transfer involving third-party entities is looked at with great care after the Carlos Tevez affair.

On a similar basis it took time for deals to be completed for Manchester City’s Eliaquim Mangala and Liverpool’s Lazar Markovic earlier in the window as guarantees on the ownership of their economic rights were sought.

Once the Premier League are satisfied with the issues around Rojo he will be granted permission to play – but until then it leaves Van Gaal without one of his key signings and a defensive headache.