Bayern Munich are considering a January move for Athletic Club defender Unai Nunez amid an injury crisis at the back for the Bundesliga champions.
Niko Kovac was already facing a selection dilemma with first-choice centre-back Niklas Sule ruled out for the rest after tearing his anterior cruciate ligament against Augsburg on Saturday.
And that was further perpetuated after Lucas Hernandez underwent surgery on Thursday on an injured ankle ligament that forced him off against Olympiacos on Tuesday.
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That has left Kovac with just one fit out-and-out senior centre-back in the shape of Jerome Boateng, though Javi Martinez, Benjamin Pavard and David Alaba all have some experience of playing that role previously in their careers.