The Scotsman made a rare unpopular decision to offload the Frenchman following a disagreement between the two.
However, Jose Mourinho is keen to bring the 23-year-old midfielder back to Old Trafford, tabling a world-record offer of £100m.
Speaking on the BBC, Ferdinand, who was at United with Pogba, recalled witnessing his talent and contended that letting him leave was a poor decision.
“The thing that stood out for me when I first met him other than he ability was his personality,” he said.
“This kid wants to be the best, he started this tournament very anxious, like a kid who had something to prove after he’d been hyped up and was worthy of that hype but he’s grown into this tournament [for France].
“His star quality was undoubted. There was not one person in that changing room who wasn’t sure. Everyone in that changing room knew that him leaving was a huge, huge error.”
To hear such outward criticism of Sir Alex is very rare, and is testament to the way players and fans alike felt about Pogba’s departure from Old Trafford.
Such frustration has been amplified over the past few years: whilst United’s midfield has struggled to find the right formula, the Frenchman has stormed to success with Juventus.
United fans will be keen to see the club’s unfair treatment of Pogba rectified, as he is set to smash the transfer record in the coming weeks for a return to Old Trafford.