The Reds turned in a poor performance in Switzerland as they blew a lead following Aaron Wan-Bissaka's red card to open their European campaign with a 2-1 defeat.
Cristiano Ronaldo scored again to break the deadlock after his return from Juventus, before Wan-Bissaka was given a straight red card for an over the top tackle after just 35 minutes.
It means Solskjaer has now lost seven of his 11 games in charge in the Champions League as Man United boss and Ferdinand says that while he has done a good job up to this point as manager, his expectations have now changed and he could face the sack just like any other manager would.
"Now it's D-Day. It's his squad, shaped by him, got the players, had a wonderful transfer window just gone. Bringing in winners and people who can change the culture of the football club."