Arsene Wenger's final visit to Old Trafford as Arsenal manager ended in defeat this afternoon as Manchester United scored a 92nd-minute winner to clinch all three points and guarantee a top-four finish.
Paul Pogba gave the home side the lead in the first half, but Henrikh Mkhitaryan's second-half equaliser against his former club looked to be enough to earn the Gunners a point.
However, Marouane Fellaini came off the bench to score in stoppage time and steal the win for Jose Mourinho's side as Wenger's youthful side were left with nothing.
Find out how all of the action unfolded courtesy of Sports Mole's minute-by-minute updates below.
It is arguably the defining fixture of the Premier League era, and for one of the men most synonymous with it, today represents his final taste as Arsene Wenger visits Old Trafford for the last time as Arsenal boss. Some of his best and worst moments have come on this ground, and while he will be desperate to end on a high, he knows that Arsenal's priorities lie elsewhere now.
We will have a closer look at both teams in a short while, but first let's check out the team news...
Well, the Arsenal lineup is very interesting indeed, but we'll start with the home side here as Jose Mourinho makes just the one change to the team which reached the FA Cup final at the expense of Tottenham Hotspur last weekend.
That switch comes at the heart of the defence, where Victor Lindelof comes in for Jones, who misses out entirely. Bailly is also absent from the squad once again, so Smalling continues alongside Lindelof at centre-back.
Sanchez has not been at his best since joining United - and so far it looks as though the Gunners may have got the better end of that swap deal - but there is no denying what Sanchez is capable of and no team will need reminding of that less than Arsenal. They will need to keep a close eye on him today.
David de Gea was exceptional at the Emirates Stadium in December, making 14 saves throughout the course of the match - the most any keeper has made this season. His performance was integral to United's 3-1 win in what was one of the games of the season.
Further forward, Ander Herrera and Jesse Lingard are both handed starts once again, which hasn't always been the case this season, while Anthony Martial and Marcus Rashford and once again forced to settle for a place amongst the subs.
It was expected that Mkhitaryan might be held back for Thursday having only recent returned to training following a knee injury, but Wenger has thrown him straight back in which is a statement that he is still taking this match seriously.
This is some place to make your Premier League debut, and with Chambers alongside him Manchester United will no doubt see that pairing and really try to get at them with Lukaku's strength. Mustafi and Koscielny have been given the day off completely, so there isn't much support on the bench should they struggle to cope with the United striker.
In all there are eight changes made by Wenger to the side which started against Atletico Madrid on Thursday, with Ospina, Bellerin and Xhaka the only players to have kept their places.
Once again Lacazette is not available in reserve for Arsenal today, but they do have Danny Welbeck, who has scored on both of his returns to Old Trafford as an Arsenal player. Indeed, no Arsenal player has scored more away to Manchester United under Wenger than Welbeck.
Indeed, even a draw would effectively be enough to take them out of reach of fifth-placed Chelsea due to their superior goal difference, but Mourinho will want the win which would take them five points clear of Liverpool with a game in hand too.
The Red Devils have jumped from sixth in the Premier League last term to second this and have also reached the FA Cup final. Victory in that would see Mourinho win all of the trophies available to him - with the exception of the Premier League and Champions League - in his first two seasons at the club.
As if losing to the bottom club wasn't bad enough, the result also gifted Manchester City the title which, while it had been expected for a long time, cannot have made things any easier for United.
In addition to the FA Cup win over Spurs, that means that United could beat every other team in the top six in the space of little more than two months with a win today, which would be quite the achievement.
Those two most recent defeats saw United crash out of the Champions League and hand Man City the title so they have been costly ones too, and Mourinho's men are today bidding to avoid back-to-back home defeats for the first time since January 2014.
The Red Devils do still have one of the best home records in the league - and boast the best home defensive record with only eight goals conceded - but defeat today would see them fall to successive home league losses for the first time since March 2014, when they lost 3-0 to both Man City and Liverpool in a row.
One thing we may not see today is a stalemate; none of United's 13 league matches in 2018 have ended all square, after the Red Devils had finished 2017 with three draws on the bounce.
Wenger lost his first ever match with the Gunners at the stadium - a 1-0 defeat in November 1996 - and he will also be keen to forget the 8-2 drubbing his side received in August 2011, a result which remains his joint-heaviest league defeat at the club.
The aforementioned 8-2 loss must surely be the worst, but the Gunners have also been on the end of a 6-1 defeat here, while who could forget Wenger standing amongst the fans with his arms outstretched after being sent from the touchline for kicking a water bottle? Add to that the 'Battle of the Buffet' and Martin Keown vs. Ruud van Nistelrooy and this really is a venue steeped in Wenger's legacy at Arsenal.
Mourinho has been glowing with his praise for Wenger this week, but he has also called the veteran boss a "voyeur" and a "specialist in failure" in the past.
Mourinho did not lose any of the first 13 meetings between the two managers, although he has since lost two of the last five as Wenger has begun to even things up a bit. Mourinho has never lost at home to Wenger's Arsenal, though.
In truth, most Arsenal fans will have given up on that a long time ago, but their other route into next season's Champions League - via the Europa League - is a difficult one now so Arsenal could be left with nothing at the end of the season.
Arsenal are currently stuck on 57 points, and they need 10 from their final four games - which come against United, Burnley, Leicester and Huddersfield - just to equal that.
Arsenal haven't lost six in a row since January 1966, and remarkably only five teams in the entire league have picked up fewer points on the road than the Gunners.
This is a difficult one to call, with Arsenal not at full strength but still having the players capable of hurting United. I am less convinced by their ability to keep them out at the other end, though, and given Arsenal's shocking away form I am leaning towards a United win.
SPORTS MOLE SAYS: Man Utd 2-1 Arsenal
Indeed, across all competitions Arsenal have lost 13 of their last 18 away games against United, winning just twice in that time, so this is far from a happy hunting ground for the Gunners.
The reverse fixture was a thrilling affair at the Emirates in December which United somehow won 3-1 despite being cut open almost at will at times.
During that time Arsenal have drawn four games and lost six from four FA Cup outings, five league games and one Champions League contest.
MAN UTD STARTING XI: De Gea; Valencia, Lindelof, Smalling, Young; Herrera, Matic, Pogba; Lingard, Lukaku, Sanchez
ARSENAL STARTING XI: Ospina; Bellerin, Chambers, Mavropanos, Kolasinac; Xhaka, Maitland-Niles, Iwobi; Nelson, Aubameyang, Mkhitaryan
Pogba himself really kickstarted the move by driving forward from midfield before giving the ball out to Lukaku, who shapes a beauty of a cross to the back post. Sanchez looks certain to score and does nothing wrong with his header, but Bellerin's last-ditch slide diverts the ball against the post. However, it then rebounds straight to Pogba, who reacts well to turn it into an empty net.
Both sides have played some good football and it has been evenly-matched for the most part, and despite going into the break behind Wenger will feel that his side are still very much in this game.
Lukaku created the initial chance with a lovely cross into the box, but Xhaka's defending has to be highlighted as he dove in on Pogba and then didn't track the United man back when he advanced into the box.
Aside from that there hasn't been much to shout about for United in terms of goalscoring chances, with Arsenal arguably creating the better openings aside from the goal.
Aside from that, Nelson and Maitland-Niles have both also been unable to hit the target with good sights of goal, but there have been enough moments for Arsenal to provide hope for the second half. They just need to be a bit more clinical in the final third.
It is all very messy in the middle of the park, but Arsenal come out with it and Mkhitaryan collects the ball just outside the area. Lindelof is not quick enough to close him down, and Mkhitaryan is able to fire his low effort through the defender's legs and into the bottom corner.
It is a classic Fellaini tactic as Young whips the ball into the big man, who produces a very good header which sneaks past Ospina and just inside the far post!
It is harsh on Arsenal, who played well and deserved something from the game, but ultimately that is now six consecutive Premier League defeats on the road.
Thank you very much for joining Sports Mole for today's Premier League clash as Arsene Wenger's final trip to Old Trafford as Arsenal manager ends in heartbreak with a late winner for United. I will leave you with our match report, and be sure to stick around for reaction too.
From me, though, it is goodbye for now!