Some might say that Manchester United’s victory over Arsenal on Sunday was very fortunate.

The Premier League leaders went to Old Trafford knowing that a victory could put the Gunners 11 points clear of their rivals. However, a sickness bug in the Arsenal hotel made players such as Per Mertesacker and Tomas Rosicky unavailable for the match as the Gunners lost 1-0. Robin van Persie’s tenth goal of the season was enough to separate the two sides, as his powerful header went over the head of English left back Kieran Gibbs, who was standing on the line.

If Mertesacker was fit to play, some would argue that his height and presence would have prevented that goal from going in. So, this leads to the question: despite Arsenal being on top of the league, are they still vulnerable at the back?

Arsenal’s method for defending set pieces isn’t exactly the what most fans would like; the zonal marking system has shown marking a part of the box isn’t as effective as man marking. However, this time last season after 11 games, Arsenal were sitting in seventh place with only 16 points to their name, conceding 11 goals. Twelve months on, Arsenal sit top, nine points better off and having conceded one less goal, which is a massive improvement. But have the Arsenal backline learnt from their mistakes last season?

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In the games against Bayern Munich (first leg) and Blackburn in the European and FA Cup last season, the Arsenal players were so determined to win that they ended up losing both matches as they committed too many men forward. The goals which Bayern scored at the Emirates last season were diabolical, as Arsenal had so much space at the back exploited. A few days before the Bayern match, the Gunners were knocked out of the cup by Blackburn after the Gunners pushed everyone up for a corner, which lead to Colin Kazim-Richard’s winner. So, after these mistakes which cost Arsenal trophies, you would think that they would have learnt their lesson going into this season.

When you look at the opening day defeat to Aston Villa when Arsenal were 2-1 down, the Arsenal defenders were pushing so far forward for their equaliser that Villa went up the other end an scored.

With Laurent Koscielny off; Per Mertesacker, Bacary Sagna and Carl Jenkinson all went forward leaving Jack Wilshere as the last man, and he was still in Villa’s half. So when Villa went on the counter, everyone in the ground knew what the outcome was going to be.

Arsene Wenger’s philosophy at Arsenal is to attack, as that is the best form of defence, but despite winning eight of their first 11 league games this season, the Arsenal defence is still prone to mistakes which could be avoidable.

A few weeks ago when Arsenal took on Crystal Palace, Arsenal were winning 0-1 thanks to a Mikel Arteta penalty, and the Gunners were in control of the game. Arsenal looked comfortable and were shutting out the Palace attack with ease.

However, with twenty five minutes to go Arsenal get a corner and within 10 seconds, Palace are on the counter attack which leads to Mikel Arteta being sent off for hauling down his former teammate Marouane Chamakh. This gave Palace the edge and Arsenal had to rely on Wojciech Szczęsny on a number of occasions to keep Palace out.

The Arsenal defence is making mistakes which need to be avoided if they want to win the league. And it’s not like they have got bad defenders playing for them, it’s the fact that the Arsenal backline feel they need to make a bursting run or go up for every set piece when they should be playing it safe - after all, playing safe wins you titles. The Manchester United team of 2008/09 is the prime example of winning the league when playing safe, due to their low scoring victories and their mean defence.

However, despite Arsenal’s occasional vulnerability at the back which has cost them games in the past, the Gunners backline have defended extremely well this season. Games against Tottenham, Liverpool, Sunderland and Swansea were all hard fought victories thanks to the Arsenal defence, as the likes of Bacary Sagna, Laurent Koscielny, Per Mertesacker and Kieran Gibbs fought like warriors to keep their opponents out.

If the Arsenal backline defend like they did in those four matches, the title could be going to the Emirates.

Are Arsenal still vulnerable at the back?

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