Has there ever been such a transformation of feelings around Old Trafford in just two weeks?
Two weeks ago, Old Trafford came to a standstill after an abysmal and limp performance against Brighton caused United to crash out of the FA Cup in their first game of the tournament. It left United with no hope, and nothing to fight for. The pessimism around the stadium at full-time was palpable.
Two weeks and two games later, that couldn't be further from the truth. Manchester United took on Manchester City at home, and dominated the game, running out 2-0 winners in a score line that flattered City's performance. United dominated the game, and arguably should have won by more.
City's loss in the Champions League to Bodo/Glimt did something to temper expectations. There were no shouts of 'United are back', no tweets telling United to 'get the contract out' Rio Ferdinand-style. It was one game, against a City side that looked shaky. Arsenal would be a wholly different test.
United victorious over league leaders Arsenal in classic at The Emirates
Carrick named an unchanged side for the game against Arsenal, and the gunners were able to field a virtually full-strength side. Arsenal took control of the first 20 minutes, and eventually made it count with a fumbled goal in just before the half-hour mark.
United were handed a gift shortly afterwards after Mbeumo got on the end of a Martin Zubimendi hospital pass and drew United level. Patrick Dorgu then gave United the lead early in the second half with a miraculous 25-yard volley, and United looked to take control.
Mikel Merino put Arsenal level again, fumbling the ball in after a chaotic corner, before Matheus Cunha produced a beautiful strike to give United the lead again late on. The final whistle blew, and the away end at the Emirates exploded. Arsenal have not been rocked like this at their home ground in years. Their first home defeat of the year, and a serious denunciation of their so-called title challenge.
Two victories, against 2nd and 1st place in the League respectively, after a dire year and a half. The tonal shift around United is absolute. Suddenly, there is something to fight for this season.
A full complement of points from two of the toughest games of the season is enough to make any team's fanbase delirious with optimism. But United's performances have been so dire for so long.
United have shown more heart in 180 minutes of football than the team did in 14 months of Ruben Amorim's tenure. United have got United fans off their seats and believing again more than Ruben Amorim ever did. With the exception of United's last gasp win over Lyon last year, it's given United fans more happiness and belief than they've felt in a long time.
United suddenly have something to fight for this season. Champions League qualification suddenly looks achievable after United have met the two best teams and won. United will continue to be tested, and a slip-up in either of United's next games against Fulham or Tottenham is likely to puncture the bullish atmosphere.
Those are questions for another day. Right now, Michael Carrick has got United fans believing again. He's transformed the outlook of the season in two weeks. It's been so long since the mood at Old Trafford could be called 'optimistic'