The two sides went into the game knowing that it would likely have a huge impact in the race for the top four and the tension around Old Trafford could have been cut with a knife before kick off.
That tension soon multiplied in the home end as Chelsea came flying out of the blocks with the returning Alvaro Morata turning a low cross from Marcos Alonso onto the bar from close range with just four minutes gone.
The away side continued to be the better team in the opening exchanges and dominated possession.
Following their early pressure though Chelsea’s tempo then dropped, with United going close themselves.
First, Romelu Lukaku saw an effort on the turn blocked, before Alexis Sanchez wasted a great chance by prodding straight at Thibaut Courtois after being well found by Anthony Martial.
- Willian's hot streak continues -
United were made to regret that miss just after the half-hour mark as Chelsea took the lead. It came from a United free-kick, with the Brazilian rising to head the initial ball clear before bursting forward on the break.
Willian exchanged passes with Eden Hazard and when the return ball set him racing away there was no doubt as to what the result would be, with Willian powering past David De Gea at the near post to open the scoring, though the Spaniard really ought to have done better.
That lead lasted just seven minutes though as United levelled as half-time approached. A nice move from the hosts on the edge of the box ended with Martial squaring for Lukaku to tuck home his first goal against a top-eight side this season.
25 February 2018
With that the two sides went in at the break level and it looked like it may stay that when the second half began in scrappy fashion.
Chris Smalling did well to prevent Alvaro Morata from having a clear sight of goal, before David De Gea unconvincingly kept out a Willian free-kick as Chelsea once again started the better side.
However, as the game went on United grew into things and began to look the most likely.
Lukaku saw an acrobatic volley tipped over by Courtois after being picked out by Alexis Sanchez, but with just 15 minutes to go, the Belgian turned provider as United took the lead.
- Lingard's instant impact -
The former Chelsea man drifted out to the right wing and swung in the perfect cross for substitute Jesse Lingard to head past Courtois at the near post to put United in front.
25 February 2018
There was still time for arguably the game's main talking point though as Morata fired across De Gea and into the far corner with just minutes to go, only for the goal to be chalked off by the offside flag, despite replays showing that there was very little in it.
In the end though it was United who emerged victorious to return to second, whilst Chelsea drop to fifth following Tottenham's win over Crystal Palace.