After trailing for most of the game, Manchester United pulled out an injury time winner to stun the Magpies and earn three points.
In this wild affair, United showed many flaws despite earning the win, as well as many strengths that helped them get the win.
Ultimately, Sir Alex is sure to have learned a lot about his team and will use the following revelations going forward in the second half of the season.
While conceding three goals can't entirely fall on one player, Jonny Evans should be given most of the blame for United's poor defensive outing in this fixture.
Despite scoring a crucial equalizing goal, Evans played very sloppily otherwise, picking up a yellow card and even putting the ball in his own net. In addition, Evans' poor marking aided Newcastle's other two goals, twice allowing Papiss Cisse open shots, which both led in some way to a goal.
With Sir Alex having given Evans a long time to prove himself, he has to be wondering whether or not he is really the type of top-caliber player that United need.
While fans continue to argue that Carrick is not the long-term solution to United's midfield problems, the English international continues to produce for the Reds.
Although he is sometimes seen as a liability on defense, his passing ability and ball awareness is priceless to United.
Against Newcastle, this was shown from his two assists: A clever flick to Robin van Persie and an immaculate aerial pass to Javier Hernandez.
Despite being considered one of the best players in the world, Wayne Rooney should no longer be considered a lock to start every game for the Reds.
With the current form of Javier Hernandez and Robin van Persie, United have shown they can win without their No. 10 playmaker. Outside of this win, United have beaten Southampton, Wigan, Liverpool and Galatasary without their 27-year-old star.
With their surplus of strikers, the club have no need to rush Rooney's recovery from injury.
After struggling at home during last year's EPL campaign, United are successfully defending their territory once again.
In 10 home games thus far, the Reds have only lost once, in a narrow 3-2 defeat vs Tottenham. Other than that, no team, including the likes of Newcastle, Fulham and Arsenal, have gotten a single point when playing on United's home turf.
With this type of consistency at home, it will end up being United's title to lose.