The 23-year-old joined the European champions in the summer on a five-year deal from Werder Bremen.
Marin told Kicker-Sportmagazin: "I signed a five-year deal at Chelsea, so there is no reason to put that into question after just five months here.
"I have also been out injured for three months. Of course I would love to play more minutes, but there are quite a few factors why I have been unable to do so.
"Rafa Benitez is a good manager and the club have put their trust in me and I have a clear idea about my future role.
"I could imagine a loan deal. It could be an ideal option to get me playing more regularly and help me with my general development, but I think at this time it is out of the question and I won't be heading back to the Bundesliga."