Manchester United are keen to bring Jerome Boateng to Old Trafford – but only on loan deal, Sky Sports News understands.
Jose Mourinho has the German international as his No 1 choice recruit - but privately behind the scenes at United, there are fears over a permanent contract for a player with a chequered history of injuries.
Boateng, 29, suffered muscle and tendon injuries over the past three Bundesliga campaigns, missing 27 games in total since December 2016.
Last season he suffered a hamstring injury in April, almost causing him to miss Germany's dismal World Cup campaign in Russia.
Boateng also missed a number of games at the beginning of the 2017-18 season due to another hamstring problem.
He returned to training last month - starting on the bench in Wednesday's friendly against FC Rottach-Egern - and remains contracted to Bayern until 2021.
But with the transfer window closing at 5pm on Thursday, Mourinho is running out of time to find a new central defender.
Privately, United believe Harry Maguire is not for sale at Leicester and as things stand, Yerry Mina's chances of coming to Old Trafford look increasingly slim.
Chief executive Ed Woodward has made funds available to Mourinho but he is determined not to pay over the odds in the current market.
But one source has told Sky Sports News that United have already had two bids turned down by Leicester for the England defender. The second bid was worth about £60m.
It is understood Leicester are in advanced talks to sign two centre-backs - Filip Benkovic from Dinamo Zagreb and Caglar Soyuncu from Freiburg - at a combined cost of about £35m.