The record transfer may have been all but agreed in principal, but the last remaining details are continuing to delay Paul Pogba’s return to Manchester United from Juventus. Pogba looks set to become the world’s most expensive player, with United said to be willing to be willing to pay around 110 million euros ($121 million) for a player who left to join Juventus for just one million euros ($1.1 million) four years ago.

However, negotiations have now stalled, according to Sky Italy and other outlets because of a disagreement over who will pay the massive 20 million euros ($22 million) fee being demanded by the France midfielder’s agent Mino Raiola. Despite having just spent 94 million euros ($103 million) on Gonzalo Higuain, Juventus appears unwilling to budge on its stance that it will not be responsible for the payment.

“Pogba to Manchester United? We will see when everything is over,” Juventus chief executive Beppe Marotta told reporters on Monday. “Right now everything has stopped.”

Given how much money Manchester United is already willing to pay, it appears unlikely that the remaining disagreements will see the deal fall apart. However, new manager Jose Mourinho has previously said that alternatives to Pogba are being considered.

One of those may now be available. Blaise Matuidi lined up alongside Pogba in France’s Euro 2016 final defeat to Portugal and is widely thought to be on United’s radar, perhaps even in addition to Pogba rather than a mere backup option. And his new manager at Paris Saint-Germain, who brought Poland midfielder Grzegorz Krychowiak with him from Sevilla this summer, has now suggested that Matuidi can leave if he so desires.

"He is a very good player,” Emery told French sports daily L'Equipe. “We have a lot of left-footed defensive midfielders. If he has the opportunity to leave and if he thinks there are too many midfielders here… But I do not want him to go.”

The Manchester Evening News has reported that Matuidi is eager for a transfer this summer in order to experience playing outside France. With two years remaining on his contract, this summer would appear to be a logical time for PSG to cash in on the 29-year-old. A fee of 30 million pounds ($39 million) has been discussed.

Mourinho has repeatedly stated that he was looking to sign four players to go into his first season in charge at Old Trafford, with a midfielder the last remaining piece following the arrivals of Zlatan Ibrahimovic, Henrikh Mkhitaryan and Eric Bailly. However, there continue to be rumors that another center-back is also on his radar.

Raphael Varane, who played under Mourinho at Real Madrid, was one man linked, but has in recent days insisted he will be staying at the Bernabeu. Now the Daily Mirror has thrown Manchester United’s name into the mix for Juventus’ Leonardo Bonucci.

The 29-year-old, who excelled at Euro 2016 for Italy and is renowned for his ability to execute unerringly accurate long passes out of the back, is a target for Manchester City and is said to have already had a 45 million euros ($49 million) bid rejected.  It seems unlikely, then, that he will be heading to Old Trafford, particularly given that Manchester United’s summer spending will already have been taken to around 200 million euros ($220 million) if Pogba arrives.