The player once dubbed the 'German Messi' has looked anything but in his first year, but it has been more to do with injuries and a lack of opportunities.
He scored in the FA Cup win against Brentford at the weekend, and there is hope it may spark him into life.
If it does then Chelsea are onto a real winner, but whether Rafa Benitez can get the best out of him or not, really isn't the point when it comes to his future at the club.
In the summer it's extremely probable a new manager will come in, with his own set of ideas and systems. If he can have the luck of staying fit, then Marin may just suit the style or preference of the new boss better than he has done with Di Matteo or Benitez.
He's clearly a talent, but to judge him on just one Premier League start all season isn't fair, nor is it to decide to sell him.
Marin's problem is there is a plethora of competition for places at Chelsea which makes it difficult to force his way in, plus in the summer, loanee Kevin de Bruyne will rejoin the fold.
It's possible Marin will find himself loaned out, but Chelsea should not act too hastily and write him off just yet; for just like he clearly wasn't rated by Di Matteo, the next manager after Rafa whoever it may be, might just find a key role for him which allows him to flourish and carve a career for himself at Stamford Bridge.
Marin will no doubt be tempted by the 'easy option' to return to Germany where he will doubtless have offers, but if he can stick it out and fight for his place for another season, he might just find his reward.
Should Chelsea hang onto Marin for another year?
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