Louis van Gaal dive was a fine portrayal of Arsenal's collapsing title pursuit

While Louis van Gaal dived, Arsenal nosedived. The Manchester United coach looked like he had ended up on the wrong end of an argument with Roy ‘Keano’ Keane as he apparently illustrated his unimpressive perception of Alexis Sanchez’s theatrical antics to the fourth official Mike Dean during the second half of his have-a-go-heroes' 3-2 win at a throbbing Old Trafford.

[MATCH REPORT: Arsenal’s title dream dented by United defeat]

[STORY: Van Gaal performs ‘Oscar-winning’ dive in front of Wenger]

Yet on Oscars Sunday, here was total football’s method actor revelling in total emotion: Van Gaal’s collapse could easily have been a withering critique of Arsenal’s faltering output in a title pursuit that may suddenly prove beyond them. That old infamous Dutch sense of humour doth come in handy now and again.

Arsene Wenger manages a side who it seems cannot escape their final destination whenever they come across meaningful moments at Old Trafford. Bad news today that could bring more distressing dispatches from the front line tomorrow. Especially when your front line has days like these: a disappearing act in Theo Walcott, a malfunctioning Alexis and little in the way of support from Aaron Ramsey.

In succumbing to a fairly wretched defeat to a home side with an average age nudging 23 - only because 34-year-old Michael Carrick was posted as an uncomfortable centre half - and no outfield player over the age of 21 on the substitutes bench, Arsenal continue to find new ways to falter at the same old joint in a rehashing of the same old story.

They have won none and lost seven of their past nine visits to Old Trafford, their very own theatre of nightmares.

Rousing though it was and a script ripe for a Hollywood ending led by the teenage wonderkid Marcus Rashford on his Premier League debut of all things, Van Gaal’s team are unlikely to be recalled in future years as United's class of 2016.

Rashford scored twice and added an assist for Ander Herrera to plunge a killer third from which they could not recover despite Mesut Ozil trying to remind his companions the importance of the occasion with a goal and a willingness to avoid this embarrassment.

Tim Fosu-Mensah, 18, and James Weir, 20, were handed time from the bench with Adnan Januzaj, 21, Memphis Depay, 22, and Jesse Lingard, 23 giving United fans more to rejoice in than just three consecutive wins for the first time since November.

This one may hurt Wenger more than their 8-2 shredding at the same venue in 2011 or a 6-1 loss 15 years ago when one considers the immaturity of the home side. Yet Wenger tried to apply some sense to a defeat that made none.

Nobody could buy that, not even the £250m Van Gaal has spent on upholstering an injured-ravaged squad, led by Wayne Rooney in a knee brace in the stands and most of which were left watching how it is supposed to be or used to be done around the old place under Fergie.

Fergie himself feasted on a small pleasurable glimpse of yesteryear when his United were in their pomp doing similar stuff to Arsenal. Witnessing Wenger’s hangdog look is unlikely to cause him much concern.

Ferguson departed the post three years ago yet Arsenal have suddenly gone a decade without a win in Salford. If Arsenal fall a point or two short in their pursuit of a first Premier League title since 2003, they can reflect at some length on what went wrong here.

It is too early to read Wenger’s side the last rites on this particular campaign, not when they are only five points off top spot, but there was a symbolism about the happenings over the weekend that will hardly bolster Arsenal’s collective psyche. It is also a timely remember of how it tends to go wrong for them at this juncture of the year when they traditionally fade before the real heat comes on.

Arsenal had it all going for them before yesterday's match. United were playing their second match in three days after a Europa League duel with FC Midtjylland as Wenger’s squad rested up after a stout if ultimately unsuccessful defeat to Barcelona on Champions League Tuesday. Arsenal were positively blooming in comparison to a United squad full of willing fledglings.

Yet Arsenal, perhaps the Premier League’s greatest flat-track bullies when in the mood on their own turf, somehow subsided with a performance Sky Sports pundit Graeme Souness described as “bordering on a joke”. He was being kind with the bordering part.

The stuff of champions was simply missing from Arsenal, who served up thin gruel. While Leicester and Tottenham found a way to win against the odds, Arsenal were simply odd, listless, anonymous, characterless. All cardinal sins at local league level, never mind in the Premier League.

Leicester, never at their best, ran to the last minute to secure a 1-0 win over Norwich on Saturday while Tottenham recovered from trailing to Swansea to come up with a 2-1 win at the same time Arsenal were losing. Mauricio Pochettino's side managed to remain two points behind Leicester courtesy of Danny Rose's winning goal. They operated with a team aged 24 years and 103 days, and the young Spurs could contribute more to Arsenal angst at White Hart Lane on Saturday.

If you are good enough, you are old enough. Against a United side adopting such a policy, Arsenal will wince at the memory of this.

Rashford has made a greater introduction into English football that Ronnie Radford’s FA Cup long-ranger for Hereford that sunk Newcastle in the early 70s. In two outings against FC Midtjylland and Arsenal, he has scored four goals.

He was helped along the way by the visiting side. When the going gets tough, the tough don’t go missing. Not faced with such decimated hosts.

Wenger’s defence remains better than the team’s.

Arsenal remain unreliable yet totally predictable. Their greatest attribute is that which suggests they continue to flatter to deceive.

On a day when the Oscars are handed out, Arsenal picked up a Razzie award for a dreadful performance.

They were merely Imposters representing a club that gifted us the Invincibles.