The 27-year-old has been linked with a switch away from Celtic
The 27-year-old is not expected to be a part of Brendan Rodgers's long-term plans in Glasgow.
As a result, the Nigeria international may be prised away and The Daily Record report that the German outfit could submit a £1.5 million bid.
But although Rodgers may not need Ambrose in the long term, the Northern Irishman could leave himself short of defensive options for an upcoming Champions League qualifier were he to sell Ambrose.
Celtic, who face Flora Tallin or Lincoln Red Imps in the first leg of a preliminary tie next week, will miss centre-halves Jozo Simunovic and Dedryck Boyata for the clash due to injury.
Consequently, the report goes on to claim that the former Liverpool boss has a dilemma regarding Ambrose and might hold off on selling him until their defence is less depleted.
The towering defender, who is stuck in Scotland due to a Visa problem, joined Celtic in 2012 from Ashdod and has since made over 100 Premiership appearances for the reigning Scottish champions, vying for a sixth successive title next term.