Leeds' move for Bayern Munich midfielder Michael Cuisance has collapsed after the player failed a medical due to a foot injury, The Athletic reported on Friday.
Leeds were set to pay £20 million ($26 million) for the French under-20 international with Bayern retaining a buy-back clause.
"The move came to a shuddering halt when scans turned up an issue with one of Cuisance’s feet," reported The Athletic.
"Leeds performed further assessments and weighed up the risk.
"After mulling the results over and taking advice from head of medicine Rob Price, they pulled out of the transfer."
Cuisance, 21, has made 11 appearances for the European champions since joining from Borussia Monchengladbach just over a year ago.
Leeds have already significantly strengthened their squad on their return to the Premier League after a 16-year absence with the signings of Spanish internationals Rodrigo and Diego Llorente and German international defender Robin Koch.