Manchester United's hopes of qualifying for the last 16 of the Champions League suffered a blow after they drew 2-2 with Atalanta on Tuesday night.
Ole Gunnar Solskjaer's men looked to have turned a corner after beating Spurs 3-0 at the weekend, but were brought crashing back to Earth by Gian Piero Gasperini's organised outfit and were fortunate to escape with a point.
Scott McTominay had a shot deflected onto the post early on and United looked stronger in the opening exchanges, but Josip Ilicic gave Atalanta the lead at the other end after 11 minutes.
Duvan Zapata made a great run into the channel and picked out the Slovenian with a cut-back, and his slow strike was somehow too hot for David de Gea to handle, and the ball trickled into the bottom corner.
Zupata had a great chance to double Atalanta's lead when United were caught sleeping at the back and the Colombian was able to run onto a long ball over the top, but he did not keep his shot down.
Atalanta continued to pile on the pressure and forced Paul Pogba into giving the ball away in a dangerous area, but Eric Bailly made a great recovery challenge to deny Zapata a certain goal.
Raphael Varane was substituted with an injury as Solskjaer's problems mounted, but United found a leveller with a fine sweeping move on the verge of half-time, with Cristiano Ronaldo slotting it home after a neat layoff from Bruno Fernandes.
The two Portuguese stars combined just after the break, with Ronaldo winning the ball high up the pitch and teeing up Fernandes, but his shot was blocked by Jose Palomino.
Zapata finally had the ball in the net after another run in behind went untracked, but the offside flag was up and United's blushes looked to have been spared, but after a lengthy VAR check, the hapless Harry Maguire was proven to have been playing the striker onside and the goal stood.
Atalanta dropped a little deeper to defend their lead as the clock wound down, with Mason Greenwood of all people blocking a stinging strike from Aaron Wan-Bissaka to come to their rescue.
United threw on Donny van de Beek (seriously) and Jadon Sancho to try and rescue a point, and finally found a way through when Ronaldo volleyed in an equaliser in stoppage time.
Solskjaer's side remain top of the group on seven points - level with Villarreal who they play next - while Atalanta remain two points behind them.
Here are your United player ratings...
Man Utd player ratings
1. Goalkeeper & defenders
David de Gea (GK) - 3/10 - Had a great season so far but goodness me, how didn't he have the strength to keep Ilicic's opener out?
Eric Bailly (CB) - 8/10 - His recovery pace helped United out of several sticky situations. One of his best performances in years and yet it proved futile.
Raphael Varane (CB) - 6/10 - Swept up well before being subbed with injury.
Harry Maguire (CB) - 4/10 - Atalanta targeted him and were rewarded with goals.
2. Midfielders & wing-backs
Aaron Wan-Bissaka (RWB) - 4/10 - Doesn't offer enough going forward and looks lost at the other end when starting higher.
Scott McTominay (CM) - 3/10 - Commentator Darren Fletcher described him as 'a competitor', which was very kind. Very lucky not to be sent off for multiple yellow card offences.
Paul Pogba (CM) - 2/10 - Deary me. Offered nothing in way of control or chance creation and was a net negative on his return to the side. McTominay was a walking red card and yet Pogba was the midfielder Solskjaer hooked.
Luke Shaw (LWB) - 5/10 - Wasn't terrible but still nowhere near his form from last season.
Bruno Fernandes (AM) - 7/10 - One of few United players who can leave with their head held high, was surprisingly substituted late on with the Red Devils chasing the game.
Marcus Rashford (CF) - 5/10 - Looked rusty in patches and is a different option to Edinson Cavani, but showed some promise in the first half.
Cristiano Ronaldo (CF) - 8/10 - Actually pressed and looked menacing even when he wasn't scoring, which is a rarity for him in 2021. Came to the rescue once again to continue his fine Champions League form.
Mason Greenwood (RW) - 5/10 - Contributed little to the game despite grabbing a fortunate assist. Tried to channel his inner Arjen Robben but Atalanta weren't falling for it.
Edinson Cavani (CF) - 5/10 - Couldn't get in the game, probably because Atalanta defended so well.
Nemanja Matic (CM) - 5/10 - Well, he wasn't as bad as McTominay or Pogba.
Donny Van de Beek (CM) - N/A
Jadon Sancho (LW) - N/A