I think the best option would be to give him a new 4-5 year contract and loan him out for 2 seasons to a team playing in the prem or La liga that's willing to play him on a regular basis.
He's 22 and 23 next season, so he really needs to play regularly. He'll no doubt be behind a lot of players next season, so what's the point in wasting his talents? let another team nurture him... and if he's good enough, in 2 years time, bring him back when he's gained experience and at the age of 24.
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