The steel hand in Arsenal's velvet glove

Almost immediately, their scepticism waned as this short, angry Frenchman ran on to the Emirates pitch and screamed at Carl Jenkinson, shouted at Tomas Rosicky and followed it up with a brutally hard — yet fair — tackle on Tottenham’s Paulinho.

In the heat of a North London derby, Flamini’s desire and rage burned brightest; it was like he was never away.

If it hadn’t been apparent before, then the Arsenal fans swiftly realised this was precisely what they have missed in the five years since he controversially walked out on the club; a fierce, devilish competitor who would halve his grandmother for the cause.

Mesut Ozil has grabbed the headlines and Aaron Ramsey the accolades, but Flamini has been quietly integral to everything Arsenal have done well this season. As the Premier League leaders head to the Etihad this lunchtime and the supreme challenge of Manchester City, the 29-year-old will be key as he looks to keep control of Yaya Toure in the hosts’ midfield.

Considering that he is giving away 14cm in height to his Ivorian opponent, you would expect Flamini to be the underdog, but he has a level of cunning and intelligence that gives him every chance of success.

Witness the way he has worked off the field. Firstly, in 2004, he used his basic training as a lawyer to explore a loophole in his Marseille contract to walk out on his boyhood club for Arsenal at a cost of just €380,000.

Flamini’s coach at the time, Juan Anigo, called it “a beautiful treason”.

Fast-forward to 2007 and Flamini was frustrated at his lack of playing time at Arsenal. The midfielder allegedly decided the best way to change that was to telephone a number of magazines and newspapers and grant them interviews explaining he wanted to leave the club, taking so much interest in the pieces that he asked for headlines to be changed.

A year later and he was playing regularly but out of contract at the end of the season. In response he demanded a substantial pay-rise — one equivalent to what he felt it would cost the club to replace him — and when it was not forthcoming, left for AC Milan.

So how did he return to Arsenal? Largely it was down to Arsene Wenger’s forgiveness, and the manager’s acceptance that former players can train with the club while they look to get back to full fitness. As Flamini did that, it became clear they were still well matched, and he eventually signed a three-year deal.

“I had unfinished business with the club,” Flamini has said. “I was not planning to sign. Milan offered me a two-year contract extension. I did not agree on it as I wanted a minimum of three-years. I am 29-years-old. I have three good years in front of me.

“So I came here. It was an important decision for me to decide where I wanted to go. It could have been Italy, Germany or England but I came to Arsenal to work with fitness coach Tony Colbert. I did that for about a month and day after day I felt better and better and it happened. I am happy I came back.”

Arsenal are happy too. To see Flamini snapping at midfielder’s heels is to be reminded of what they have lacked. And when he cajoles — forcefully or otherwise — his team-mates it is not hard to see why Wenger has so much time for his fellow countryman.

“We had no real defensive midfielders before he arrived,” replied Wenger when asked by the Irish Examiner yesterday what he valued in Flamini.

“All our players in the middle of the park are players who like to attack and are creatively focused. Mathieu is more focused on defending well, helping out. That part of the contribution is what he has brought to the team and the squad.

“Do I like it when he tells his team-mates what to do? It is good he is concerned by that because in our team most of the players are always only concerned by how quickly we can go to the other goal. Someone who has that focus helps us to stabilise our defensive record. He has certainly contributed to our defensive record.”

Flamini enjoys the dirty side of his job. With sleeves rolled up — or even snipped at the elbow — he is a scuffler in a team of artisans, a pint of stout in a world of pina coladas.

Back in September, the internet was awash with stories Flamini told Stoke’s Irish player Marc Wilson if he fouled Ozil again ‘I will blind you’. It has never been substantiated, but the fact it was believable tells you all you need to know about Flamini’s approach. His decision to cut the sleeves on his long shirt — going against club tradition — drew Wenger’s ire and also shows Flamini does not necessarily do as he is told. As a leader, that is nothing to be ashamed of.

“I’m trying to be a leader,” he told the Examiner. “Why do I tell my team-mates what to do? Well everything I do, I do it very naturally. I am trying to play my game and help everyone on the pitch. The spirit in this team is amazing. It is such a team effort, we try to help each other and defend together. That makes a difference.

“Now we play City and Chelsea — they are really big games, but we are getting used to it. It is such a big period for us. With City, Yaya Toure and Fernandinho are a really good partnership and it will be a good, interesting game. But as a team we have the quality to go over there, play our football and get a result.

“What would be good for us from these games are two victories, but we know that won’t be easy as City and Chelsea are big teams with a lot of quality. It will be very interesting to see where we are after these games.”

Flamini himself has had a circuitous route back to north London. Marseille-born, he only spent a year in the first-team before departing for Arsenal. Having started a legal degree because he was unsure he would make it as a pro, he realised as he was on a meagre trainee’s contract he could leave France for a nominal ‘training fee’ rather than extend his deal with Marseille.

As Anigo said at the time, “Flamini has character. He’s intelligent and he knows the system. He’s more calculating than you think.” Arsenal already know that, to their cost. Between 2006 and 2008 Flamini had formed a fine midfield with his close friends Cesc Fabregas, Aleksandr Hleb and Tomas Rosicky. On the day Flamini rejoined Arsenal, Fabregas tweeted a picture of the four of them together in the tunnel at the Emirates, with a quote from Flamini saying, ‘I have a great relationship with Tomas, Cesc and Alex both on and off the pitch.’ Yet that was not enough to keep him in London when he felt his talents were not being suitably recompensed. The media interviews he gave at the time were calculated and he left for Milan, where injury restricted him to 128 appearances in five seasons.

There he won Serie A 2010/11 and departed on good terms as he returned to Arsenal to take his time over his next move before realising it was right in front of him.

Now the club are five points clear at the top of the Premier League and Flamini — the only player to win a trophy with the club, the 2005 FA Cup — knows he can help the club end their long, painful trophy drought.

“It’s a great feeling to be five points clear but the Championship will be long and there is a lot of games to play,” he said.

“Now we have to focus as a team game after game, as all the games are quick. It will be a busy period so we have to stay focused. But we are Arsenal, a big team with big ambitions.”

And in Flamini, Wenger may well have the man to help achieve those ambitions.