He states that the midfielder has not enjoyed living in Manchester and has personally asked for a move to a different climate - with an expectation that Manchester City will honour that request.
In his initial report, Atletico Madrid were named as being the main club interested in acquiring his services. The Spanish champions even posed the idea of including one of their captains, Saúl Ñiguez, in a potential swap deal.
However, Castles now says that Atletico need to solve their FFP situation, which brings a move for the previously linked Joao Felix back onto the table. There could be a situation were he is offered in a swap deal instead of the aforementioned Ñiguez.
Aston Villa's Jack Grealish is Pep Guardiola's number one target however.
With the 25 year-old 'extremely high’ on Manchester City's list for the summer transfer window, Etihad officials are claimed to firmly believe that there is a ‘real possibility’ of signing the England international and pairing him alongside Phil Foden - in a midfield duo that could possibly drive the club forward for the next decade or so.
Speaking of the pairing, Jack Grealish was full of praise for Manchester City's rising star Phil Foden in his pre-European Championship press conference on Wednesday afternoon.
“He’s an unbelievably talented player, he just loves football," Grealish said with a smile.
"Trying to get him on the coach after training is hard work! But it's just the way we like to handle the ball and take it in any type of situations and thats why there's been some comparisons with Gazza."
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