Marin who joined Chelsea last summer from Werder Bremen has remained un-used on the bench for the Blues for the entirety of the season and with Leverkusen striker Andre Schurrle joining that not going to change.
They have instead decided to let the German international spend the next season in the La Liga where he will play for Sevilla.
This will mean more playing time for Marin and he could become an important asset for the Spanish club who finished in 9th last season if he can manage to recapture the form which led to the signing of him last time round.