The Japan playmaker has failed to failed to live up to expectations since joining from Borussia Dortmund in 2012.

The 25-year-old has started just 13 Premier League games this term, leading to speculation he could be unsettled at Old Trafford.

And Napoli boss Rafael Benitez is understood to be keen on bringing Kagawa to Serie A in the summer, with the club aiming to make a push for the title next season.