Diego Simeone recently admitted that Saul asked to leave Atletico Madrid. Having fewer minutes and not always playing in his position has reportedly forced the player to make the decision to look for options elsewhere.
They are various clubs that have been linked with a move for Saul. Barca, Liverpool and United are three of the best-placed suitors to be able to bring in the midfielder.
Media in England - namely the 'Daily Mail' - place Saul closer to Old Trafford than anywhere else. They report that United are capable of going all out for the Spaniard. The Red Devils have reportedly done the maths and they feel that 52 million euros will be enough to convince Atletico, even though his release clause is set at 150 million.
Another Atleti player that has been heavily rumoured with a move to the red side of Manchester is full-back Kieran Trippier. The same source explains that any move for either player will be made completely independently, and won't be part of a joint deal.