Martin O'Neill had just delivered his post-mortem on Sunderland's latest defeat of a difficult campaign, a 3-1 reverse which leaves the Wearsiders just one point clear of the relegation zone, when Van Persie's contribution to his team's downfall prompted a shake of the head and an admission from the Northern Irishman that the former Arsenal forward is becoming United's irrepressible talisman.
A first-half goal, a second-half assist for Wayne Rooney and a centre-forward's masterclass was the sum total of Van Persie's afternoon.
The Dutchman has now scored 15 goals in 21 games for United and his strike rate is outpacing Cristiano Ronaldo's 14 goals by this point in December when he ended the 2007-'08 campaign with 42 in all competitions.
And having benefited from the best years of Larsson's prolific career during his five-year spell as Celtic manager, O'Neill insists that Van Persie is already in the same bracket as the Swede.
"I think so, absolutely," O'Neill said. "United have paid close on £30m for a player who had just one year left on his contract at Arsenal, so that might tell you how valuable they perceive him to be, but it's not just a perception. The reality is that he has been fantastic.
"He can get goals out of very little. It looks like nothing is happening, you have players there in the area, but all of a sudden, he has opened up a gap. Just look at the third goal. We would say we didn't defend brilliantly, but he would say it was great play, fantastic play, and you always felt that United would give themselves a big edge by getting Van Persie.
"That's not to say that (Carlos) Tevez and (Sergio) Aguero are not great players at Manchester City, because they are, but this extra boost that United got in pre-season would have been psychologically massive."
Although Van Persie's goal output is left in the shade by Messi, who is approaching 90 goals in the calendar year for Barcelona and Argentina, O'Neill believes that the pair have a similar effect on their respective teams.
"Would Barcelona have the same effect if Lionel Messi didn't play?" O'Neill said. "The number of goals he has scored is incredible. They are a very talented team, but without him, you don't know what will happen because Messi is their talisman. With players like Van Persie, you always have a chance of winning football matches when you have that calibre of player in your side.
"We are making judgments before Christmas here, but if he stays fit that will make a massive difference to United's challenge."
Against Sunderland, Van Persie set United on course for the victory which restored their six-point lead over closest challengers City following their 3-1 win at Newcastle earlier.
In truth, they should have won by a much greater margin, with Van Persie, Rooney and Ashley Young all spurning enough chances to walk away with hat-tricks.
Young and Patrice Evra had already seen clear chances go begging before Van Persie opened the scoring on 16 minutes when, after Young had escaped Carlos Cuellar and Sebastian Larsson, he struck from close range following John O'Shea's miscued clearance from Young's cross.
United poured forward and more chances were missed until Tom Cleverley scored the goal of the game when he rounded off a one-two with Michael Carrick – who could miss the Christmas fixtures with a hamstring injury suffered before half-time – with a first-time shot from 15 yards.
"The goal from Tom Cleverley was a marvellous piece of interchange play," said Alex Ferguson. "First-time finish, one-touch finish, a really superb goal and it epitomised the way we were playing at that point."
United's failure to build on their early lead until the second half denied them the emphatic victory their dominance deserved, but Rooney made it 3-0 on 59 minutes following the contribution from Van Persie which prompted O'Neill's praise.
Having received the ball from Young just inside the penalty area, Van Persie appeared to have nowhere to go as Cuellar and Titus Bramble attempted to crowd him out, yet he shimmied through a tiny gap between the Sunderland defenders and crossed for Rooney, who stroked the ball home at the far post.
Top at Christmas usually bodes well for top spot in May, but United defender Phil Jones places no significance on his team's position.
"I don't think we can think like that. Last season was a prime example so we've got to keep on our toes and play the way we did today. Hopefully we will maintain our good form and that will see us through." (© Daily Telegraph, London)