Leeds United were dealt a blow after Bayern Munich midfielder Michael Cuisance failed a medical last week.
The France youth international landed in Yorkshire on Wednesday for his medical ahead of a move to Elland Road after both clubs agreed a £20 million deal.
However, scans turned up an issue with one of his feet, and Leeds pulled the plug on the deal immediately.
They performed further assessments and weighed up the risk, but decided against signing Cuisance after mulling the results over and taking advice from head of medicine Rob Price.
He returned to Bayern and Marseille made a move despite thinking they had lost him to Leeds.