Ruben Amorim made four changes from the team that lost against Arsenal in midweek as Leny Yoro made his full debut, Amad Diallo started and both Lisandro Martinez and Kobbie Mainoo returned from suspension.
The changes weren't enough to solves Unied's set-piece woes, which continued when defender Nikola Milenković headed the visitors into the lead within 90 seconds, the third goal they have conceded from a corner kick in the past week. Amorim's side responded better than they had done against Arsenal though and went close twice as Rasmus Hojlund almost connected with a dangerous cross into the box and Amad fired a low effort at goal after a clever free-kick routine.
United would soon find themselves level through Hojlund, who was perfectly positioned to fire a rebound into the back of the net after a clever pass from Manuel Ugarte had carved the Forest defence apart. Forest continued to have joy though and twice went close when Jota Silva headed an effort against the crossbar and when Murillo drilled a low effort just wide of the target.
Bruno Fernandes almost gave his side the lead in spectacular circumstance before half-time when he smashed a free-kick at the crossbar, but there was nothing to separate the two teams as they went in level at the midway point of the match.
Forest had scored early in the first-half and they had one early into the second as well when Morgan Gibbs-White sent a swerving effort at goal that somehow went beyond Andre Onana to give the away side the lead for the second time. It wasn't long before things got even worse for United either, when they failed to clear their lines and Chris Wood headed in a third at the back-post after some more calamitous defending and poor goalkeeping from Onana.
The away side continued to push for a fourth goal that would have killed the game off, but were made to pay for their wasted chances when Fernandes buried an effort from the edge of the box after some selfless build-up play by Amad.
United pushed hard for an equaliser as Diogo Dalot headed at goal and Amad fired another effort at goal that was blocked well by a Forest defender, but there was no way back as Amorim suffered his second successive defeat as head coach.
Here is how we rated the United players in the 3-2 home defeat to Nottingham Forest:
Rooted to his spot for the first goal and would have saved the second if he hadn't have moved. It didn't get better when a third sailed over his head either.
1. Andre Onana - 3
Rooted to his spot for the first goal and would have saved the second if he hadn't have moved. It didn't get better when a third sailed over his head either. | Manchester United via Getty Images
A solid enough outing on his full United debut. The first two goals weren't his fault but he was bullied by Chris Wood for the third.
2. Leny Yoro - 5
A solid enough outing on his full United debut. The first two goals weren't his fault but he was bullied by Chris Wood for the third. | Getty Images
De Ligt wasn't that bad himself but has to take some of the blame for what was a calamitous defensive performance from the start.
3. Matthijs De Ligt - 5
De Ligt wasn't that bad himself but has to take some of the blame for what was a calamitous defensive performance from the start. | Manchester United via Getty Images
A really poor performance by his typically high standards. Beaten with ease for the first goal and watched on as Wood made it three. Almost redeemed himself with a spectacular effort in added time.
4. Lisandro Martinez - 3
A really poor performance by his typically high standards. Beaten with ease for the first goal and watched on as Wood made it three. Almost redeemed himself with a spectacular effort in added time. | AFP via Getty Images