Manchester United vs. Arsenal: 6 Things We Learned

A Robin van Persie header was enough for Manchester United to beat Arsenal and drag themselves back into the title contention.

Heading into this match, the Gunners had not lost an away game since March. However, after a grueling week in which they faced both Liverpool and Borussia Dortmund, Arsene Wenger's team never quite hit their stride at Old Trafford.

Although Arsenal improved to put the United goal under some pressure in the second half, the champions stood firm to show they will not give up their crown without a fight. This could be a turning point in David Moyes' first season in charge.

Go to the next slide to discover the first of six things we learnt from this game.

Strikers Win Games

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Strikers are so often the difference.

Prior to the match, it was clear who would be United's danger-men: Robin van Persie and Wayne Rooney. So it proved. That talented pair combined to create the game's only goal, with Van Persie rising highest to meet a perfectly delivered Wayne Rooney corner.

Even though Arsenal probably edged the midfield battle, United's clinical front two won the match.

On a day when Olivier Giroud struggled to make an impact, Arsene Wenger could turn only to Nicklas Bendtner on the substitutes bench. United, on the other hand, had the prolific Javier Hernandez as an unused substitute.

Come January, Arsenal must improve their striking options if they are to sustain their challenge.

Mesut Ozil Is Not Perfect

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ST ALBANS, ENGLAND - NOVEMBER 05: Mesut Oezil of Arsenal takes part in a training session at London Colney on November 5, 2013 in St Albans, England. (Photo by Ian Walton/Getty Images)

This was probably Mesut Ozil's poorest display in an Arsenal shirt.

Although he has been heralded as one of the major reasons for the Gunners' recent revival, his performance at Old Trafford fell well below the standards expected of Arsenal's record signing.

His passing radar was unusually inaccurate and he seemed to duck out of a presentable opportunity to head Arsenal's equaliser.

Arsenal supporters' joy at Ozil's arrival should not render him exempt from criticism. Today, he was not good enough.

Arsenal Miss Theo Walcott

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In the first half, Arsenal were far too narrow. With Santi Cazorla and Aaron Ramsey drifting infield in the flanks, the centre of the pitch became congested and easier for United to defend.

It was telling that as soon as the second half started, Ramsey was being instructed by Arsene Wenger to pull wider, stretching the play. The late introduction of Serge Gnabry also helped Arsenal's attacking efforts.

The truth is that Gnabry is the only pure winger currently available to play. After the international break, Theo Walcott will return, offering pace and penetration on the flanks.

At Old Trafford, he was much missed.

Thomas Vermaelen Still Has Something to Offer

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When the news broke that Per Mertesacker would miss the game with flu, many Arsenal fans worried about the prospect of Thomas Vermaelen returning to the side. This was his first Premier League start of the season.

However, the Arsenal club captain didn't let his team down. He put in a dogged, disciplined display that shows he remains a valuable member of the squad and a reliable back-up.

However, Per Mertesacker Is Vital to Arsenal's Hopes

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Despite Thomas Vermaelen's competence, Arsenal badly missed Per Mertesacker.

It's not only that Mertesacker would have been stationed in the near-post area from which Robin van Persie rose to head the winner.

Arsenal missed Mertesacker's sheer presence in the side. Although Vermaelen is the club captain, his authority has long since been undermined by being dropped from the side. Mertesacker is, in many ways, the team's true leader. He offers inspiration and organisation, and would surely have galvanised Arsenal today.

This isn't the first time this season the big German has missed a game due to sickness. One wonders if a flu jab might be worth the investment!

United Can't Be Written off

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Write off Manchester United at your peril.

Despite a shaky start, United are now just five points off top spot and have climbed above neighbours City in the table. With this big victory under their belt, the champions are starting to build an ominous amount of momentum.

However, Arsenal should not be too disheartened. They lost this game by the narrowest of margins, and still top the table.

The true measure of Arsenal's title challenge will come from how they respond to this setback.

What did you make of the game? Are United back in the title race? Let us know below.