Nicolas Gaitan
Nicolas Gaitan have been linked with Manchester United in recent years Reuters

The future of Benfica's Nico Gaitan has once again been thrown into question, with Portuguese newspaper A Bola saying the Argentinian will be moving to either Manchester United or Valencia – with some claiming that he made an agreement to join the Old Trafford outfit in May.

The 27-year-old midfielder has long been linked with a move to Louis van Gaal's side, and in June agent Jose Iribarren said they had been making renewed efforts to secure the services of his client.

"Everything is possible. There are negotiations pending with Manchester United. The will of the player is that everything runs as smoothly as possible. We are awaiting a response," Iribarren told Portuguese radio station Antena 1.

Spanish newspaper AS confirmed this news in July, revealing that when Atletico Madrid asked Benfica about the possibility of signing Gaitan to replace the outgoing Arda Turan, the Portuguese giants said that they had to meet his €35m (£24.7m, $38.5m) release clause, as they already have a verbal agreement to sell him to Manchester United if Angel di Maria leaves Old Trafford.

Rafael's agent Cassiano Pereita added more fuel to the flame by revealing Manchester United had been negotiating a swap deal between the Brazilian right-back and Gaitan – before his client opted for a move to Lyon instead.

"Benfica and Manchester United are in negotiations over Gaitan and one option includes Rafael joining Benfica. Rafael wants to join Benfica. It's a big European club. If the talks proceed, it will not be difficult to reach an agreement," Rafael's agent said as quoted by Goal.

But with Di Maria already having made the move to Paris Saint-Germain, A Bola have reopened the transfer saga, claiming the future of the Argentinian will either be at Valencia or Old Trafford.

The Portuguese newspaper says that the Premier League giants have had an agreement in principle to sign Gaitan for €21.2m since last May – but it is still uncertain whether Van Gaal will finally decide to go ahead with the move. If Van Gaal opts against it, A Bola believes the player will go to Valencia.