Jose Mourinho's attempted move for Tottenham Hotspur defender Toby Alderweireld was reportedly blocked by Manchester United's board.
The Red Devils were linked with an array of centre-backs last summer, Alderweireld being among them, but did not land any of their targets.
Mourinho hinted earlier in the season that a failure to further strengthen at the back was to blame for his side's slow start to the campaign, which ultimately cost him his Old Trafford job in December.
According to The Mirror, the former Real Madrid and Chelsea manager attempted to talk the club into snapping up Alderweireld from Tottenham, with the Belgian defender available for a cut-price fee as his contract was close to expiring.
United's board vetoed the move for tactical reasons, however, as they were supposedly concerned he could not play in a four-man defence.