The Turkey international has failed to settle at Real Madrid but the German champion is not actively seeking to re-sign the 23-year-old midfielder.
The Turkey international only left for Real Madrid last summer, but has struggled to nail down a regular berth in Jose Mourinho's starting lineup and has been repeatedly linked with a move away from the Bernabeu this summer.
Dortmund has been mooted as a possible destination and while Watzke is reluctant to rule out re-signing the midfielder, he revealed that it is not exactly on the cards.
"Sahin coming back to us is not planned, either by him or us," Watzke told Sport Bild. "However, he' s a boy with a Dortmund past and he came from our youth team, so I would never rule out a return."
Madrid paid a reported 10 million euros for Sahin, who still has four years to run on his contract with the Liga champion.
Follow GOAL.COM USA on