When Arsene Wenger's lineup for Arsenal's FA Cup replay with Swansea revealed Jack Wilshere would likely be playing as the most advanced midfielder, with Santi Cazorla shifting to the left wing, I was admittedly skeptical of the effectiveness of the change. I realize it's a shift some Arsenal fans have been calling for for some time- many believe Wilshere's best position is the #10 role and Cazorla excelled mostly as a winger prior to joining Arsenal.

However, I've always been impressed with Cazorla's clever movement and ability to find space between the opposition defense and midfield when he plays centrally off a main striker. That Wilshere is already a very good player with loads of potential is clear, but I thought the Gunners would miss Cazorla's close control and passing vision in crowded spaces around the box. Wilshere, I thought, was the archetypal box-to-box midfielder, strong in the tackle, energetic, able to beat opponents with his dribbling and possessing a wide range of passes. Playing him off of the striker, I assumed,

Wilshere injected a directness and pace into Arsenal attacks they don't possess when Cazorla plays attacking midfield. Time and again last night he was able to get the ball in the final third, turn and use his pace and skill to advance beyond Swansea's two holding midfielders. This would force one of Swansea's center backs to step to him and leave space for balls to be slotted through to Giroud, Walcott and Cazorla. A combination of poor finishing, bad luck and last ditch Swansea defending kept Arsenal off the scoreboard for 86 minutes (before Wilshere himself broke the deadlock) but Wilshere was creating good goalscoring chances seemingly at will.

Cazorla plays patiently as the #10, keeping hold of the ball and waiting for angles in which he can use his excellent vision to provide defense splitting passes. He sets a patient tempo to the Gunner's buildup play, allowing them to get numbers forward and play intricate passing combinations around the penalty area. At times this style works excellently but it can also allow the opposition time to recover into deep, compact defensive positions where they can prevent gaps from opening up for Arsenal to play balls in behind.

Wilshere's style is more explosive- he looks to receive the ball, beat a man and slip a teammate through on goal. With Wilshere as the #10, Arsenal's play in the attacking third is much more vertical and much faster. His first instinct when he gets on the ball is to face goal and run towards it. Anyone who has watched Lionel Messi knows that a central attacker who constantly looks to run towards goal at pace is a terrifying prospect. Although it would be ludicrous to compare Wilshere to the Ballon D'or winner at this stage in his career, he brings that same narrow-minded desire to get at the opponents goal Messi brings to Barcelona.

Of course this was just one game against a distracted opponent that was not at full strength. Against certain opponents Cazorla may well still be the better option at the #10 role. However, Wilshere's ability to play that position well will offer Arsenal a different option in that area of the field at a time when Cazorla's form has dropped over recent weeks. Since registering a hat trick and an assist in the Gunner's 5-2 win in December over Reading, he has just one assist and no goals in the last six games. The option of playing Wilshere higher up the field and Cazorla on a wing will allow Arsenal to alter it's approach in the final third and make them a less predictable opponent.

West Brom and Arsenal will look to get back to winning ways when they meet at the Emirates Saturday afternoon. Arsene Wenger's side are winless in their last three league games and sit 10th in the table, their worst start to a season in 18 years. Steve Clarke's Baggies have lost their last two but have had more to celebrate this season- despite the recent defeats West Brom are off to their best start to a Premier League campaign. They find themselves 5th in the table, level on 26 points with fourth place Spurs and 3rd place Chelsea.

Wenger will have to deal with several injuries to first team regulars. Laurent Koscielny, Theo Walcott and Lukas Podolski will all be sidelined while Bacary Sagna is also doubtful. Carl Jenkinson will replace Sagna at right back. Aaron Ramsey may be given the start on the right in the absence of Walcott with Alex Oxlade-Chamberain expected to fill in for Podolski on the left. Wenger also has Tomas Rosicky and Gervinho available. He could opt to play Rosicky on a wing or in the hole behind Giroud and push Cazorla wide.

Boaz Myhill will fill in for the Baggies at goalkeeper for Ben Foster who is recovery from groin surgery.

A Clash of Styles
This game will showcase a clash of two very different playing styles. Arsenal build attacks patiently from the back, move forward as a unit and retain possession. West Brom defend deep and look to counter rapidly. Arsenal lead the league in possession, averaging 59.9% per game while West Brom are fourth from bottom with 43.5% per game.

Expect West Brom to drop their wide midfielders Odemwingie and Gera alongside Yacob and Mulumbu in defense to create a second bank of four. Jenkinson and Gibbs will join in the attack for Arsenal from their outside back positions, pushing Odemwingie and Gera further towards their own goal. Ramsey will likely tuck inside from his right midfield position, creating space for Jenkinson to overlap. Jack Wilshere will push forward towards Cazorla in possession and look to link defense to offense. The Gunners will look to create short combinations of passes around the penalty area and find gaps in West Brom's back four to slip the ball through. They need to do a better job of turning possession into genuine goal scoring chances. During their current three game winless streak their opponents have taken more shots on target in each game despite Arsenal winning the possession battle in all three games and completing more passes in the final third.

With Jenkinson and Gibbs pushing forward, West Brom will look to quickly counter in the space behind the two Arsenal outside backs when they regain possession. Shane Long will likely float into these wide channels to provide one option for an out ball. Gera and Odemwingie will also try to quickly break in behind Jenkinson and Gibbs. It'll be Morrison's job to quickly transition forward in the middle of the pitch and link with Long. With Wilshere moving in to more advanced positions in possession, Arteta will be responsible for slowing down counterattacks, particularly by denying Morrison opportunities to get on the ball in space. The Spaniard's positioning was incredibly poor on Swansea's opening goal last weekend when he completely switched off on attacking midfielder Michu and left him unmarked just in front of the Arsenal back four.

The screenshot below shows Arteta 15 yards to the left of Michu, moving into an area Arsenal already had well covered. Chico is able to clip a pass into Michu, forcing Vermaelen to step to ball and leave space in behind him. Michu plays a simple on-two with Luke Moore, breaks past the Dutch center back and coolly finishes the breakaway. Had Arteta been in the correct position in front of the back four, Vermaelen who have never had to step out, allowing space behind him for Michu to run into (in fact Michu wouldn't have even received the ball). Arteta will have to do a better job tracking Morrison when West Brom look to break.

Central Midfield Zone
As mentioned above, defensively West Brom will likely drop their wide midfielders Gera and Odemwingie alongside holding midfielders Yacob and Mulumbu to create a midfield bank of four. Against Chelsea's 4-2-3-1, Shane Long dropped alongside James Morrison to pick up Chelsea's two holding midfielders, Mikel and Romeu on that day, and left the center backs unmarked. Both Mikel and Romeu like to sit in front of the back four and circulate the ball sideways; neither are particularly strong at linking defense and attack either with their dribbling or forward passing. Their reluctance to push forward meant Long and Morrison could defend them fairly easily while still remaining high up the pitch in good counter attacking positions when West Brom regained possession. It also meant West Brom had a spare holding midfielder so Chelsea's attacking central midfielder (both Hazard and Sturridge played there for the Blues) was outnumbered. West Brom had a spare center back as well so in the central attacking zones Chelsea were outnumbered 2 v. 4. As a result, the Blues lacked a vertical passing option and were forced to play the ball sideways.

Arsenal will pair Jack Wilshere alongside Mikel Arteta at center midfield. Wilshere is more of a box-to-box midfielder than either Mikel or Romeu and will push higher up the pitch and do a better job of linking defense to offense. The Baggies will therefore have to decide if they want Morrison to track the forward movement of Wilshere so that they have a spare holding midfielder and can defend the dangerous Santi Cazorla 2 v. 1 higher up the pitch. If they do that Long will drop in and sit on Arteta. The danger for West Brom of playing like this is that they could get pushed too deep defensively and not have an out ball when they retain possession. Therefore I'd expect Morrison to pick up Arteta, leaving a 2 v. 2 match up higher up the field between Cazorla-Wilshere and Yacob-Mulumbu.

Arteta's role circulating the ball and dictating the tempo of the game is crucial for Arsenal. Team's that have kept him off the ball have had success against the Gunners- their ball movement becomes far too slow without his involvement. He averages 88 completed passes per game, second in the Premier League only to Michael Carrick. In games he's completed fewer than 80 passes Arsenal are averaging only 0.75 points per game (1 win, 3 losses, 3 draws) and 0.57 goals per game. In games he's completed more than 80 passes they're averaging 1.63 points per game (3 wins, 1 loss, 3 draws) and 2.5 goals per game. Clarke will therefore likely put an emphasis on using some combination of Morrison and Long to keep Arteta off the ball and prevent Arsenal from getting in any type of rhythm in possession.