He'll be United's central focal point for at least a month now.
RVP's first goal in United red was a thing of beauty, a piercing strike on the half-volley near the edge of the penalty area that saw Fulham keeper Mark Schwarzer still starting his lunge as the ball starched the net.
Watching van Persie hit such a fierce-but-controlled shot off a short hop brought to mind the late savant David Foster Wallace's description of watching a professional tennis player deal with a topspin shot while coming in on it in footnote 17 of his epic essay The String Theory:
"(I)magine the hardest-hit grounder of all time coming at you at shortstop, and you not standing and waiting and trying to knock it down but actually of your own free will running toward the grounder...to strike it hard and reverse its direction and send it someplace frightfully specific and very far away -- this comes close."
That is what world-class strikers in football are capable of, and it is perhaps van Persie's greatest gift: picking corners off half-volleys and other awkwardly placed passes.
In short, he finishes.
The addition of van Persie to the already powerful United side was analyzed by some as money spent in the wrong place. United already have a special striker in Wayne Rooney through whom most of their offense flows.
Meanwhile, United lost their first game of the season primarily because a spate of injuries forced Sir Alex Ferguson to entrust midfielder Michael Carrick with the chore of marking Everton's Marouane Fellaini on a set piece, with disastrous results.
The logic, then, was that the £24m transfer fee United paid for van Persie might better have been spent shoring up the midfield or the back line.
There are three reasons why that logic fails and why the addition of van Persie could be United's key to reclaiming its place atop the Premier League. They were all borne out on Saturday.
First, if Manchester City's title last season proved anything, it is that competing at the highest level in both the Premiership and the Champions League requires having more than one superior attacker.
You want to argue that Chelsea won the Champions League only on Didier Drogba's scoring? OK. But you could hardly call Chelsea's run to the title "textbook." And they were not kicking the tires on Hulk this summer because scoring does not matter.
More indicative of the new economy in elite football was Manchester City's plan, i.e., buy a great striker. Then buy another great striker. Then one more, and one more after that.
Carry Sergio Agüero, Mario Balotelli, Edin Dzeko and Carlos Tévez on the same roster, and figure out the playing time and the ego issues as they arise.
Call City's last-ditch comeback win on the final day of the 2011-2012 campaign lucky if you like. But City scored two goals in the final five minutes of their season, two goals they absolutely had to have, because Balotelli, Dzeko and Agüero were on the pitch at the end.
The second reason why adding van Persie could make all the difference for United is pretty simple.
Rooney sustained a nasty gash to his right leg in Saturday's fixture with Fulham and is projected to miss about a month.
Without van Persie, Rooney's absence would have left United clinging to the hopes that Shinji Kagawa could continue to score twice a game for the foreseeable future.
Instead, United now have the luxury of giving van Persie the next stretch of games without Rooney in the side to let him do what he does: score goals without worrying about teammates and their need for the ball.
The last reason why signing van Persie may help United take back the Prem?
This is the league's leading scorer joining Rooney on a team that lost the league title on what?
This was the move that could win United the title.