Mathieu Flamini is ready to prove that he is up to the physical and mental demands of replacing the injured Francis Coquelin in defensive midfield for Arsenal.

Flamini started only his fourth game of the season in Tuesday’s vital 3-0 home win over Dinamo Zagreb in the Champions League – with Mikel Arteta also out injured – and he admitted that match fitness was an issue for him.

Arsène Wenger said that Coquelin would be unavailable for 12 weeks and Arteta is expected to be sidelined for a month – both were injured in Saturday’s Premier League defeat at West Bromwich Albion.

The manager has Aaron Ramsey back to fitness after five weeks out with hamstring trouble and he made his comeback as a 64th-minute substitute against Dinamo in a wide midfield role, working off the left, although his heat map showed that he drifted into central areas. This is where Ramsey feels most comfortable. Wenger must decide whether a central partnership of Ramsey and Santi Cazorla provides sufficient defensive balance.

Wenger’s other option is to play the defender Calum Chambers in defensive midfield and he brought him on in the position for the final eight minutes against Dinamo. It is Flamini, though, who is in possession of the shirt and he intends to rise to the challenge of doing the job during a congested period.

“Football is a competition, it makes you better and stronger,” Flamini said. “I have an opportunity to be back in the team and I will try to prove every game that I can be in the team. Can I play twice a week for three months? I think I can but now it is my job to prove it.

“Fitness is hard to maintain. For an athlete, if you don’t play every week, it’s not easy because the more games you have in your legs, the better you become. You gain in confidence, you become better physically, so the possibility to have game after game is obviously going to be good for me.

“It’s a lot of pleasure for me that I get back into the team. The season is always very long so sometimes you have to accept being on the bench but sometimes you have the opportunity to prove you are still there and can still play in the Arsenal team. I really enjoyed the Dinamo game.”Flamini talked up Mesut Özil, who starred against Dinamo, and he noted the “nice surprise” of seeing the German open the scoring with a rare header.

But where Flamini was concerned, it was business as usual. He leapt into his first crunching tackle in the fifth minute, his first touch was a lay-off that he bumped with his chest and, after half an hour, he had been fortunate to escape a booking for a late challenge on Paulo Machado and he had caught another Dinamo rival with a stray elbow. He also played a part in Özil’s goal.

Flamini never holds back and his relish for the forthcoming assignments was clear – including the do-or-die final Champions League group tie at Olympiakos on 9 December, in which Arsenal have to overturn the 3-2 defeat that they suffered against the Greek champions at the Emirates Stadium to progress on the head-to-head tie-breaker. They must win by two clear goals or by a scoreline of 3-2, 4-3 and so on. A 3-2 victory would suffice as Arsenal have the superior goal difference.

“It’s going to be a great atmosphere over there, we definitely know it is not going to be easy but we have the quality and team spirit to do it,” Flamini said. “We definitely can do it. We played beautiful football against Dinamo and scored three goals. Why not go to Athens and win by two goals?”