The game looked done and dusted - Manchester United commanding a 2-1 lead at Leicester City and playing some of their best attacking football of the season.
Enter Harry Maguire. Just when you thought United had maintained the gap to their noisy neighbours, a stunning cross from Marc Albrighton found the Leicester stalwart who converted from close range.
Chris Smalling executed some rather questionable man marking, struggling to keep tabs with an injury and David de Gea didn't inspire confidence with his timid positioning.
That's all by-the-by when you consider how many chances United had to put the game to bed, though.
By the time Juan Mata had whipped home a sensational free-kick to put the Red Devils 2-1 up, they still had a hatful of chances with which to kill the game.
One fell to the feet of Anthony Martial who, given his form so far this season, you'd bet your house on scoring when he stood 12 yards out and completely unmarked.
However, despite beating the entire Leicester back four, he lost his nerve in the face of Kasper Schmeichel and inexplicably shovelled his effort into the crowd.
He could at least take salvation in the face of Jesse Lingard's shooting, mind. Another winger in good form recently, Lingard showed shades of Dele Alli v Stoke City in 2016 when he had his chance on Schmeichel.
Rounding the Dane and with the goal at his mercy, the 25-year-old struck the post and will be reliving the gaffe for quite sometime.
Both chances have something rather surprising in common and that's Romelu Lukaku.
The Belgian isn't renowned for his passing and creativity, he has a rather average four assists this year, but found himself pulling the strings against the Foxes. It didn't go unnoticed by fans either who treated his spell of passing as if a secret talent had emerged.
Check out the two killer passes and reaction below:
All in all, Lukaku contributed four 'key passes' during the game and delivered one of his finest performances in a Manchester United shirt even if there wasn't a goal to top it off.
His hold-up play can often leave a lot to be desired but this shows a new side to the forward that could be very useful going forward.
As a lot of the supporters said, had Martial and Lingard had their shooting boots, Lukaku could have won them the game.
Do you think Romelu Lukaku should start over Zlatan? Have your say in the comments section below.