It was a frustrating day for Arsenal and their supporters in their away derby game against Brentford FC. The newly-promoted side claimed their first-ever victory in the Premier League as they defeated Arsenal by 2-0.

photo credits: Brentford [via Twitter] & Getty Images

The Gunners looked like they are going to repeat last season's bad performance in this campaign which has been giving their manager a lot of concern. Their defeat today placed them at the bottom table of the Premier League.

However, here are the five reasons why Arsenal lost today's match:

1. Arsenal's formation Was Overpowered

photo credit: SofaScore

Mikel Arteta's 4-2-3-1 formation cannot thrive against a team that fielded her midfield with more than four players which was what Brentford did against them today. At many times in the game, the Bees looked dangerous whenever they press the Gunners on possession. Thomas Frank did a very neat job of outclassing Arsenal's tactics.

photo credit: Getty Images

2. Absence Of Arsenal's prolific strikers

photo credit: Getty Images

Arsenal missed the qualities of Aubameyang and Lacazette on the pitch today which was one of the reasons they were not clinical. Arteta said before the match that both strikers were unavailable because they are feeling unwell which is all he can say.

So, the Arsenal manager used some young attackers to lead his line as Balogun Folarin, Gabriel Martinelli, Smith-Rowe all started the game.

Arteta will be hoping to have his both strikers available for the next games.

3. Arsenal's Last Season Defensive Problems Still Persist

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Despite the presence of the club's record signing Ben White on the pitch today, Arsenal's defense is still as worse as the previous season. Brentford attackers were given too much space to explore as the gunner's defenders couldn't deal with them.

Ben White had one of his worst time out tonight as he lost duels on his debut: he had 45.5% duels won (5/11) and 42.8% aerial duels won (3/7) according to match statistics.

Callum Chambers and Pablo Mari's performance was also nothing to write home about. Nevertheless, Arteta is required to work on his defensive issues before their next games. Hopefully, Gabriel Magalhaes would have returned.

4. Bernd Leno is out of form

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The German goalkeeper conceded two goals today which he could have done better with as the goals were too cheap to concede. Arteta will need to speak with the 29-year-old and also drill him ahead of the upcoming games this season.

5. Arsenal's Offensive Problems

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This is another problem part of the way Arsenal has been playing lately. Their indecision in the final third is among the things stopping them to score goals. Arteta seriously needs to work on this if they are to turn things around before this season gets out of hand.

Arsenal's next games are against Chelsea and Manchester City which is going to be tough.

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