The midfielder has been highlighted as a potential transfer target for the Reds in the upcoming summer window.
Per AS in Spain, the club view him as the ideal candidate to be Virgil van Dijk's long-term successor.
The Dutchman is out of contract in the summer, but he is expected to agree to a new deal.
Even if Van Dijk does stay at Liverpool, they may sign Bade to bed in over time.
The source adds that Bade was the subject of interest from Stuttgart and Roma this summer.