There had been mounting speculation as to whether Wayne Rooney and Robin van Persie can work as a successful partnership.
But after seven goals in their first two games as a combo, this could be the best strike-force in Europe—beware Chelsea!
Will one be able to accept a downgrade of prominence? Can they get on the same wavelength quickly enough? Have they got the right chemistry?
All these questions had to take a prolonged backseat because of the gruesome leg injury that kept Rooney out for over six weeks.
So all eyes were on United's recent trip to Newcastle and their subsequent home game with Stoke.
The main problems to come out of these games were for the likes of Roberto Mancini, Arsene Wenger and Roberto Di Matteo, who saw two world class strikers gel instantly.
Rooney's two game return has seen him yield two goals and three assists, while the flying Dutchman has also added one more to his league tally of six, along with an additional two assists.
A huge banana skin at St James' Park, that ended in a 3-0 rout, was trumped by a four goal demolition of a miserly Stoke defence that prides itself on clean sheets.
They say good things come in threes and that's exactly what Sir Alex will be hoping for as they head to top-of-the-table Chelsea as underdogs on Sunday afternoon.
One thing is for sure, this game will not end up in a 0-0 draw.
Both teams are iffy at the back, with each fullback eager to maraud forward at any given opportunity. Each has conceded two goals in the Champions League this week, although one result was significantly better than the other.
Is Rooney a better player with van Persie?
So given the fact that both teams are going to concede, the strikers are going to be where this game is won or lost.
Fernando Torres has shown renewed confidence in front of goal, but is still far from prolific with Eden Hazard and Juan Mata providing the main impetus.
But if United is given space to play and able get in behind Chelsea's defence, a shootout will certainly favour the men from Lancashire.
Many thought the arrival of van Persie may neglect Rooney's impact in the game, but it's actually had the reverse effect.
The England international has freely admitted his willingness to revert to a midfield role to prolong his career in the future, but that won't happen for a few years yet.
Rooney is a striker and still one of the very best in the world.
The introduction of van Persie has allowed the 27-year-old to take up the false-nine role that a certain player named Messi has adopted so successfully.
This is exactly how he will hurt Chelsea because it's so difficult to pick up.
Too far advanced for midfielders, too deep for defenders—it's the perfect position for him.
Speculation may suggest Rooney could be on the bench this weekend as United goes for a more cautious approach, but don't bank on it.
Rooney is the key to a United victory this weekend and will continue to thrive playing just behind his new partner.
Prediction - Chelsea 2 United 3