Arsenal cannot rely on producing goals of the season every week. Olivier Giroud’s scorpion flick on Sunday was an astonishing way to end an incisive counter-attack. But even as Arsenal’s season stabilises again, with two league wins following two league defeats, there is a serious question to ask: how do they play their best football without Santi Cazorla?

The Spanish midfielder underwent surgery on the plantaris tendon in his right ankle in Sweden on 7 December. He will not return until the middle of February, at the earliest, robbing Arsenal of their midfield brain, the man who makes the whole team tick.

Cazorla might not be Arsenal’s best player but he is certainly their most important. Any Arsenal player will confirm this and will routinely describe Cazorla as the very best that they have in training.

The problem for Arsenal is that Cazorla is so good that the rest of the team has grown dependent on him for direction and control, for finding the forwards early and in space. Take Cazorla out of the team and Arsenal can still break forward at speed but they cannot pick their way through a clever defence, not in the same way.

So since Cazorla first started to feel his ankle in October, Arsenal have only beaten the teams that you would expect them to beat. Their last six Premier League wins, without Cazorla, have come against Sunderland, Bournemouth, West Ham United, Stoke City, West Bromwich Albion and Crystal Palace. Their four harder games, Tottenham at home and Everton and both Manchester clubs away, have produced just two points.

In early December Wenger said that Cazorla’s absence would force the team to play in a new way. “Losing Santi not only puts pressure on some players, but you have to find a new balance again,” he said. “He was our deep playmaker, a guy who all our defenders thought ‘where is Santi?’ Without him, you need to find new ways to build the game up.”

The evidence of the last few months is that Arsenal’s new ways are not as good as the old ones. Granit Xhaka impressed on New Year’s Day with his long passing, prompting Wenger to hail his “exceptional distribution”, but he cannot run the game from tight spaces like Cazorla can.

Last season Arsenal lost Cazorla to a knee injury on 29 November, an injury that likely cost them the title. Had Cazorla stayed fit through the season their results would not have dropped off and they could have exerted enough pressure on Leicester City to force a mistake.

As Arsenal now face the prospect of another title challenge lost because of their one-man dependency, they have to think seriously about signing a replacement. Cazorla turned 32 last month and even though Arsenal are going to extend his contract into next season, there can be no guarantees about his fitness and availability any more.

The problem is that Cazorla is such a unique player that he is difficult to replace. There is a reason that Real Madrid spent £30million on Luka Modric. Arsenal could look back to Spain, at a player like Roque Mesa at Las Palmas. But if they want a midfielder who can control the game from the middle, take the ball in tight spaces and play incisive passes, but who already knows the Premier League, there may be an answer at Stoke City.

Joe Allen has shone since joining Stoke from Liverpool in the summer but he showed at Euro 2016 that he can play at the highest level. Jurgen Klopp was not the right manager for him but Wenger would be. Allen’s clever passing style make him a more natural fit for Wenger’s Arsenal than his compatriot Aaron Ramsey, whose high energy running looks strangely out of place now in this team.