The 24-year-old arrived at Stamford Bridge in a £7 million deal from Werder Bremen last summer, but after initially impressing during the club's pre-season tour of the United States, Marin's participation was hindered by a series of niggling injuries.
He made just six Premier League appearances and featured in another 10 cup matches but never sufficiently impressed either Roberto Di Matteo or Rafa Benitez enough to command a regular starting slot.
Compatriot Andre Schurrle's signing means there is even more competition for positions in attacking midfield roles, and it always seemed likely Marin would depart at some stage this summer.
Ideally, the club would have been wise to cash in on the player but a 12-month loan arrangement with Sevilla has been agreed, with Los Nervionenses attempting to fill the void left by Jesus Navas's departure to Manchester City.
It will also be interesting to see whether Marin's loan will act as a sweetener with Sevilla, with Chelsea said to be chasing the Rojiblancos in-demand central midfield player Geoffrey Kondogbia, according to Sky Sports' Giscard Gourizro.
Previously, Marin had been dubbed the "German Messi" earlier on in his career after some scintillating displays in the Bundesliga for both Borussia Monchengladbach and Werder Bremen, but persistent injuries stifled his development and has long seen him fall out of Germany coach Joachim Low's national team plans.
After a disjointed couple of seasons, Marin will hopefully find some form and fitness in La Liga. Sevilla finished a disappointing ninth in last year's Primera Division, and any rebuilding will need to start without star striker Alvaro Negredo, who is expected to seek a move away from the Ramon Sanchez Pizjuan Stadium, according to Sky Sports.
From here, it is difficult to envisage any future for Marin at Chelsea, with Schurrle, Eden Hazard and Victor Moses already ahead of him in the pecking order and Brazilian youngster Lucas Piazon rated highly.
However, if Marin can rediscover some of the performances which made him one of Europe's most sought-after stars, then he may well be worth bringing back into the fray in someway down the line.
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