Are United ready for Wenger's tactical rethink?

Analysis

Arsène Wenger was christened Le Professeur by the Arsenal players when he arrived at the club. It seems the university graduate has come up with another successful formula. Arsenal's switch to 4-3-3 has reaped impressive dividends with the team winning all four matches this season scoring 15 goals in the process.

The stimulus appears to have been last season's two Champions League ties against today's opponents, Manchester United, when his midfield two were overrun. Wenger's new formation features a third central midfielder usually Alex Song, in a holding role. Song does not just protect the central defence, he also gives freedom to his fellow midfielders, and eases their workload.

Cesc Fàbregas, Arsenal's creative font, will miss today's match with injury but explained: "For the last two years I was finishing games really, really tired because I was defending, I was attacking, I was pressurising, and usually there was just two of us in the middle against three from the other team. It was tough. In this position I don't have to run as much. I have my own zone, a little bit to the right. When you play 4-4-2 you have to go left, right, everywhere."

Abou Diaby is likely to deputise for Fabregas today, with Denilson making up the midfield trio. The key, though, is Song, who is revelling in the responsibility, and perhaps flourishing in this specific role. "He is important," said Wenger. "He smells where to be on the pitch which is the main quality of a midfielder."

Song, who described his main task as preventing couter-attacks, said: "We still pass the ball as people expect Arsenal to, but when we lose it everyone closes the ball down quickly. Maybe we didn't do that so well last season."

An unexpected side-effect is that the midfield are providing most of Arsenal's goals with the forwards scoring just three, one of them a penalty. "In this formation we create good space for the midfielders to run into the box," said Wenger, alluding to the mobility of his front three. He added: "Our strikers provide more than they score."

The weakness is that the full-backs have a heavy load. With a narrow midfield they must provide attacking width, but can lack defensive support. Today's match may turn on whether United, who conversely have moved to a more traditional 4-4-2, can expose that dual-role, or whether Arsenal's midfield trio can control the game.