Marotta concedes the former Tottenham midfielder doesn't fit into their playing system.
He said, “The important term is 'functional.' Football is full of these situations, where players are signed who are then not functional to the tactical system or team he is placed into.
“We signed Eriksen in January for €20m and an excellent bargain on the transfer market, a great opportunity, but naturally the coach has to make his evaluations and has the right to choose his line-up.
“If we reach January and the player does not play regularly, so asks to be sold, we will deal with the situation and do so without the slightest bit of controversy.
“Naturally, we always try to improve and make the most of opportunities on the transfer market, but the problem is finding players who fit the team and genuinely would improve us. This was an operation on the transfer market that was positive, but simply not fully functional to the technical and tactical vision."