Arsenal came back from 2-0 down to grab a point against West Bromwich Albion. A key half time switch to 4-4-2 changed the game for Arsenal, even though they went two goals down.
Both teams set out in a variant of 4-5-1. Arsenal played their usual 4-2-3-1, with Aaron Ramsey providing the link between midfield and attack, while West Brom set up in a 4-3-3/4-5-1 that looked to defend deep and use the pace of Jerome Thomas and Peter Odimwingie to attack on the break. Before the game could settle into any sort of pattern, West Brom scored from a corner that had major defensive issues. Sebastien Squillaci lost his man on the throw in preceding the corner. Koscielny had to head out of play, and then the two, along with Manuel Almunia, failed to organise the defense. Aaron Ramsey marked Steven Reid, but lost the ball, leaving the Albion defender to have a free header from the middle of the penalty box. It was poor play all around, and Arsenal were shell shocked.
Albion were then able to drop deeper, and make Arsenal break them down. They worked hard to close down the space in the final third, and make it difficult for Arsenal to pass the ball. They were camped out in their final third for most of the first half, and as the Chalkboard below shows, they were deep and narrow, based on their interceptions and tackles.
This has been a traditional problem for Arsenal; when the face teams that defend deep and narrow, they are forced to play wider, and cross the ball into the box. Arsenal's crossing is generally poor, and that was reflected in the first half. Despite having 74% possession in the first half, just one chance was created, and it came from a cross. Ramsey should've finished from 3 yards out, but he was not the only one culpable in a first half to forget. With Albion closing down the Arsenal players in the final third, and without the pace of Theo Walcott or Cesc Fabregas' ability to break down teams, Arsenal looked sluggish, and it was again another game where they passed the ball a lot, and had a lot of possession, but failed to find a cutting edge. When Arsenal are in form, they play a very quick tempo, and generally have less passes because they're creating chances; out of form, they play like they did today and against United. Lot's of possession, lot's of passes, little penetration.
High Line
Arsenal, whether full pressing or false pressing (which is when one player closes down), like to play a high defensive line. This line suits 3 out of the 4 defenders at the club: Both Thomas Vermaelen and Laurent Koscielny prefer to win the ball back quickly, while Johan Djourou is comfortable playing a high line or deep line. Sebastien Squillaci, however, doesn't like to play a high line because of his lack of pace. Subsequently, when partnered with Koscielny, who doesn't like to play deep, mistakes are made, and usually pacey players exploit the Arsenal back line. Several times Peter Odimwingie was just offside, and Arsenal could've been punished more on the counter attack. As it was, a West Brom counter exploiting the high line and space behind Sagna should've made it 2-0. When Squillaci failed to deal with a simple long ball, and got into a mix up with Almunia, Odimwingie finished from 30 yards. Squillaci was beaten by the high line; worried about Odimwingie's pace, he let the ball bounce, and got into a mix up that lead to Arsenal being 2 down.
Switch to 4-4-2
Arsene Wenger, to his credit, was proactive about Arsenal's struggles. Usually, he waits until an hour to make a change, but knowing that his team was facing one that was well organised, and on a slow pitch, he removed the increasingly useless Denilson and replaced him with Marouane Chamakh, adding Arsenal another target in the box, one that is 6'3. Nasri, who has good defensive skills, dropped deeper and Ramsey pushed wide, with van Persie nominally playing as a striker, but roaming around the pitch. Bendtner came on for Ramsey, and cut inside, giving Arsenal another option in the box. Arsenal's play, although uncharacteristically direct, became more penetrative. It was also predominantly from the left, because Bendtner was cutting in, and because Gael Clichy is the better attacking full back. For West Brom, Jerome Thomas, playing on the right, offered a counter attacking option but not a defensive one, while Marek Cech, a full back by trade, helped out on the right. By getting the ball wide, Arsenal were able to play around the West Brom defence, which lead to more gaps, and meant Arsenal played more in the final third than they had in the first half.
Both goals came from the left; the first was a nice bit of interplay from Chamakh and Arshavin; the second a cross knocked down by Bendtner for van Persie to prod home. Arsenal, playing Nasri and Wilshere as the two holding midfielders had trouble with West Brom on the counter, but they pressed forward, and forced West Brom to drop deeper. Whereas before West Brom were passing in the Arsenal midfield, and constructing counter attacks, they started to aimlessly play long balls, letting Arsenal push higher up and become fairly comfortable defensively, considering that they were chasing the game.
Conclusion
For Arsenal, the switch to 4-4-2 was key in their comeback. It allowed more targets to get into the penalty box and with Arsenal struggling to play through West Brom, direct football was the only option that they had. Often Arsene Wenger gets criticised for being stubborn and not changing the system, but today he was proactive and got Arsenal back in the game. West Brom's closing down fell off as well, which also helped Arsenal get back in the game, as did the increased pressure, which forced West Brom to play long balls towards Fortune rather than constructively counter attack through Jerome Thomas. Overall, it was good managing from Wenger, and Arsenal deserved their point.
Whether Arsenal switch to 4-4-2 when Cesc Fabregas is out remains to be seen, but it certainly is an option when Arsenal are playing poorly because they have the options of Chamakh and Bendtner to change the game.