The former Germany goalkeeper left Werder Bremen last May to pen a four-year deal with Hoffenheim worth €3 million (£2.6m) per year - reportedly at the expense of becoming Iker Casillas' deputy at Real Madrid.
However, he has featured just 10 times in the league, and his position at Rhein Neckar Arena now looks untenable following Heurelho Gomes' loan arrival from Tottenham and Muller's latest admission.
"All Hoffenheim players will still be contracted to the club in the event that we are relegated to 2. Bundesliga with the exception of Tim Wiese," Muller told reporters on Friday.
Wiese was recently dropped by Hoffenheim coach Marco Kurz on the grounds that the 31-year-old was struggling to cope with pressure, while he was also fined by his employers for being kicked out of a party.
His side are currently 17th in the Bundesliga standings and are 11 points adrift from safety with only 11 matches left to play in the present campaign.