If, at the start of this season, you had attempted to predict Arsenal’s central midfield duo heading into the final month of the campaign, the combination of Francis Coquelin and Santi Cazorla would hardly have been your first on your list.

The former was way down the pecking order, and spent time out on loan at Charlton midway through the season, while Cazorla had established himself as an attacking midfielder, more at home in the three of Arsenal’s 4-2-3-1 system.

But football is never predictable, and while the likes of Mikel Arteta, Mathieu Flamini, Jack Wilshere and Aaron Ramsey would have been among the favourites to play those deeper roles, Coquelin and Cazorla are currently the men in possession.

Francis Coquelin

Initially, Coquelin played as Arsenal’s sole holding midfielder with Cazorla just ahead, sometimes alongside Ramsey in a 4-3-3 system. But Arsene Wenger has often decided to tilt the midfield trio to change the balance in the centre, and allow Mesut Ozil to play in his favoured No 10 role. Therefore, increasingly Cazorla has been fielded even deeper, alongside Coquelin in front of the defence.

While an unexpected combination, Coquelin and Cazorla provide everything you require from a midfield duo. The key, of course, is finding the right balance between defence and attack, between ball-winning and ball-playing. These two provide both aspects: Coquelin is the destroyer, the feisty defensive midfielder recording incredible tackling statistics, while Cazorla is the playmaker, dictating the rhythm of the game and distributing the ball effectively into the final third.

Coquelin’s ball-winning has been particularly impressive, because this wasn’t previously considered one of his major strengths. The Frenchman was a neat, tidy and efficient holding midfielder who positioned himself intelligently without the ball. He still boasts that quality, but he’s now added ferocity and power to his game, evidenced by his tackling statistics.

In terms of tackles per game, Coquelin is in the top five players in the Premier League, alongside Lucas Leiva, Pablo Zabaleta, Morgan Schneiderlin and Nemanja Matic - he’s proved himself fully capable of playing in defensive midfield at this level. Since Christmas, he’s made both more tackles (68) and more interceptions (70) than anyone else in the division. His defensive performance in Monday’s 3-1 win at Hull (Fig 1) was particularly good, with his tackles (green) and interceptions (blue) often taking place high up the pitch.

Fig 1

Cazorla’s quality was never in question, though perhaps Arsene Wenger might be a little surprised at how effectively he’s adapted to the deep role.

Among a series of outstanding performances this season, his display at Manchester City (Fig 2) in a memorable 2-0 victory was arguably the finest midfield performance of the Premier League season. He scored the opener from a penalty and assisted Olivier Giroud’s second from a free-kick - but we all knew about his quality in the final third. What was more impressive was Cazorla’s ability to dribble past opponents when he won possession, crucial for the counter-attacking game Arsenal utilised. He completed 10 dribbles, eight in his own half.

Fig 2

He also scrapped effectively in deep positions, completing three interceptions (blue), two tackles (green), five clearances (purple) and one block (yellow) - not bad, for a natural playmaker.

Fig 3

The crucial thing is that Coquelin and Cazorla have functioned well as a duo, and help each other in different phases of play. The former has rarely been isolated ahead of the defence because his colleague's positioning has been very disciplined, while Cazorla doesn’t have sole responsibility for starting passing moves, because Coquelin is entirely comfortable in possession.

Wenger has a range of options heading into the final five games of the season, and with Wilshere and Arteta set to be available for the run-in, the Arsenal manager will have to make some tricky choices. Coquelin and Cazorla, though, are probably playing too well to drop.