Ronaldo or bust?
As Old Trafford bounced along to Viva Ronaldo in the final seconds of this contest Ole Gunnar Solskjaer must have been thanking his lucky stars that Manchester United found the funds to bring the 36-year-old back to the club this summer.
For 94 minutes Ronaldo had been quiet against Villarreal, a team he had scored 13 goals against for Real Madrid, but when a chance fell his way deep in stoppage time he was never going to squander it.
Ronaldo fired in for his fifth goal since returning to the club and a disjointed, poor United display was papered over once again by the brilliance of one man.
United's failure to get more out of him for 94 minutes should be a concern, as should a performance that saw all that attacking talent fail to string any meaningful combinations together, but at the end none if really mattered. United are back in control in this group thanks to Ronaldo - and that is why he is back.
Playing like this United shouldn't trouble the top of the Premier League or win the Champions League, but with Ronaldo you just never know.
A set play set-piece?
The free-kick that led to United's equaliser was their best attacking position of the second half, so when Bruno Fernandes clipped it to the edge of the area for Alex Telles there were a few bemused glances as Old Trafford waited for the ball to drop.
But Alex Telles had already shown he can strike a clean ball, sending in a couple of dangerous corners in the first half, and his accuracy on the volley was stunning, arcing the ball from just outside the post to just inside.
We might not know if this was a pre-planned move or if Fernandes just saw Telles lurking in space, but the two are close friends and regularly work together at Carrington, while United have appointed a set-pieces coach this season.
Maybe this move was the brainchild of Eric Ramsay, who isn't solely charged with stopping United conceding from dead-ball situations. Before the match Solskjaer had warned of Villarreal's inventive set-pieces, so it would have been particularly pleasing to see his own team score from such a move.
Pogba's attacking intent
Twice in the first four minutes of this game United attacks saw Paul Pogba as the most advanced forward, making runs beyond the Villarreal defence. On 12 minutes, as if to emphasise the point, he was flagged offside as United again looked to find him in a goalscoring position.
To put that into context, the man Pogba had technically replaced in this system was Fred, who has been flagged offside four times in 127 games for United. It's hard to ever imagine the Brazilian being the most advanced attacker in this side.
So the intent with which Pogba carried out the role was impressive and he was given that freedom due to the unique role played by Diogo Dalot (see below).
Given the lack of fluidity in United's game it's hard to say the move had been an overwhelming success, but it was certainly a signal of intent from Solskjaer to try and play a more attacking midfield.
Dalot struggles to master new role
When Dalot put the afterburners on to offer Mason Greenwood a pass on the overlap in the first 20 seconds of this game it looked like he was going to produce the kind of attacking display that we rarely see from Aaron Wan-Bissaka.
But that run turned out to be an outlier. Dalot had a difficult evening against the lively Arnat Danjuma, but he was also struggling to fully graps the positional requirements asked of him.
When United had control of the ball he would often move into a central midfield role next to Scott McTominay, allowing Pogba to get further forward and giving the midfield a little more control. Then when Villarreal had a goal kick United would line up in a back three, with Victor Lindelof, Raphael Varane and Alex Telles picking up the three attackers and Dalot helping to press, before having to drop in when play developed.
That meant Lindelof moving wide to mark Danjuma, but there were times when Lindelof had to frantically wave Dalot back into position at right-back and it was no coincidence so much of Villarreal's attacking play came down that channel, including the move that lead to Paco Alcacer's goal.
De Gea's form
United's first-half display is not one they will want to revisit anytime soon, but David de Gea was arguably the only player to emerge from the wreckage with any credit.
The Spaniard is enjoying an excellent start to the season and he made four saves before the break to make sure United were level at half-time, when they really should have been behind.
His second stop from Danjuma and his saves from Alcacer and Yeremi Pino were very good and he deserves credit for another impressive showing. Ronaldo stole the headlines, but this win owed an awful lot to De Gea.
