Robin Van Persie and Wayne Rooney up front, it is a partnership right out of your fantasy football team; It can't possibly fail right?
Between them the pair scored 57 goals in the Premier League alone in 2011/12, and United fans should well be savouring the thought of the pair taking on defences next season.
But for the Dutchman who so desperately wants to add a title winners medal to his collection, the move is no sure thing.
Samir Nasri showed Arsenal fans why he was justified in making his move to Manchester City last season, ending the season as a Champion, and Van Persie will be keen to do the same.
Had Van Persie moved to City, the odds on the boys in blue retaining their title would have shortened even further than they are. Adding last year's Golden Boot winner to their ranks would have given United a task surely too difficult to overcome, but his signing for United keeps the battle balanced finely at 50-50.
It really could go either way, and whether the title lands on red or blue next season will likely go down to the wire once again. City will be formidable opponents, and will no longer have the self-doubt which caused them to falter last season.
The underlying problem currently at United is not a lack of goals, it is their midfield. They were dominated home and away by Yaya Toure last season in the league when they clashed with Manchester City, and their problems were exposed in Europe, particularly against Athletic Bilbao.
Until the club really solve their problems in that area, even Robin Van Persie may not be enough to lead them to the Premier League title. There are some who would argue Arsenal's midfield is stronger than United's especially in the wake of the signing of Santi Cazorla.
The good news is that there is still time for United to make additions and sign a new central midfielder, and if both Tom Cleverley and Anderson can stay fit the issue will not be as bad, but that too remains a gamble based on last season.
So Van Persie has taken a little bit of a chance joining United who also ended the season trophyless last season, but with no satisfactory bids from City forthcoming he had little options to go elsewhere.
It is a gamble from his point of view because if he does not win trophies at United, he will become a laughing stock at The Emirates. The Arsenal crowd hero-worshipped their captain, and had he stayed at the club it would have been the safe option, but he now faces a hate mob for his every return to the stadium.
Time will tell whether the aggravation is worth it for the 29-year-old, but equally had he stayed at Arsenal it could have been a decision he regretted, especially after seeing Cesc Fabregas, Samir Nasri, Thierry Henry and Gael Clichy all leave the club to win major honours. Even Emmanuel Adebayor won a Cope del Rey medal during his loan spell with Real Madrid.
So either decision would have been a gamble, but he is not the only one, Manchester United have taken a calculated risk of their own on the player.
By committing an expected transfer fee of £24 million, the highest in Europe for a striker this season, plus his high wages on top - rumoured to match Wayne Rooney's, financially the club have taken a leap of faith.
Anything less than a title winner's medal will be seen as a failure at Old Trafford by the club this coming season as they strive to win their 20th league crown. But the biggest calculated risk is the injury factor.
In the eight years he has played for Arsenal he has featured in just 60 per cent of matches. In 2007-08 he featured in just 15 league games and 2009-10 just 16. Last season he was far more consistent, starting 37 of Arsenal's 38 games and coming on as a substitute in the other one.
United will hope this is a sign he is finally over his injury struggles, and they surely will put him through his paces when he undergoes his medical, but the fee and his wages are still a risk for a 29-year-old. If his problems recur then the laughter from North London will be heard all the way from Manchester.
There is talk too about Javier Hernandez being forced out by the Dutchman's arrival. United must ensure this is not the case, as while Van Persie very is much a man for the present, Hernandez, 24, has many more years to offer than the new arrival.
Manchester United have only spent more than £20 million twice on players age over 27, on Juan Veron and Dimitar Berbatov. Neither of them were spectacular successes. Sir Alex Ferguson will hope this deviation from his usual policy of signing younger players is a gamble worth taking, and the pair can celebrate with silverware next May to prove both club and player were right in making such a bold move.
Will the signing pay off for club and player?
image: © cactusbeetroot