Rio Ferdinand slammed Manchester United's direction following the "embarrassing" Premier League loss to Burnley at Old Trafford on Wednesday.
Goals from Chris Wood and Jay Rodriguez condemned a woeful United side to a deflating 2-0 home defeat in Marcus Rashford's absence.
The result left Ole Gunnar Solskjaer's men six points adrift of fourth-placed Chelsea and some 30 points behind leaders Liverpool, who beat them 2-0 at Anfield three days earlier.
Ferdinand, a vocal supporter when Solskjaer was named manager on a full-time basis in March, admitted the Norwegian deserves scrutiny and was scathing in his assessment of the club's transfer market moves since Alex Ferguson's retirement.
"I have played with Ole, he is an ex-team-mate of mine, but the results have not been good enough," the former Red Devils defender told BT Sport.
"He has had some key players get injured but, with the big amount of money spent on this squad, you would expect more in reserve.
"You look at some of the players that have come in – [Marcos] Rojo, [Radamel] Falcao, [Marouane] Fellaini, [Morgan] Schneiderlin, [Memphis] Depay – were these players ever Manchester United players, really?
"Who is buying these players? The manager coming in who wanted them for now, or the club buying for now but also future-proofing?
"£600m roughly has been spent on this squad and the most impressive players this season have been the homegrown talent.
"That speaks volumes about the recruitment. It tells you how shoddy it has been.
"Look at Liverpool, they buy the best players to fit in their system. It is not a short-term fix. Total opposite end of the scale here."
United have now won just two of their past seven matches in all competitions, and the mood at Old Trafford was summed up by the sight of supporters pouring through the exits before full-time.
"I'm embarrassed. It's embarrassing to be here," Ferdinand continued.
"Not just about the team performing, I don't see what's coming next, I don't see a pathway, I don't see a target being set on the wall and saying we're going to get to that and this is how we're going to get there."