Mertesacker admits it's been a study trip.
He told BILD: "Werder Bremen has a very good youth system and with Thomas Schaaf (technical director) someone who brings in new structures.
"I talked to him and thought about what we can do together as far as players are concerned."
Asked about loaning Arsenal players to Werder, Mertesacker added: "Let's see what happens. That was just an exchange of ideas."