The moment Matteo Guendouzi convinced Unai Emery he had the right mentality to play a key role at Arsenal this season came before a ball was even kicked.

As the 19-year-old completed his £7million move from Lorient on July 11, Guendouzi was due to join up with the France squad for the Uefa European Under-19 Championship in Finland taking place later that month.

The tournament ran from July 16-29 and so his involvement would have meant missing out on much of a hugely transitional summer as Emery began the sizeable task of transitioning from Arsene Wenger’s 22-year tenure.

It was also the next step in a flourishing career with France’s younger age groups but the midfielder turned down the chance to represent his country, focusing instead on making the most of a fresh start at his new club.

“The first impression from him is very good,” Emery told Standard Sport. “We saw this from the first weeks of pre-season when he arrived here and started training.

"For example, his very big decision to decide not to play with the national team in the summer because he wanted to stay and work with us to show his capacity in pre-season. He earned the possibility to take minutes in the first XI.

“His adaptation was very quick. Now his progress is very good. He is very young. We played with Lucas Torreira and Guendouzi as midfielders at Manchester City. He is a very young player, his present is very good but his ambition is to grow a lot with us and become an important Premier League player.”

City thoroughly outplayed Arsenal last weekend but Guendouzi’s performance stood out from a sea of mediocrity. He won the ball back as many times as his more-vaunted midfield partner Torreira (nine) and ended the game with a 91.2 per cent pass completion rate, making more passes in the opposition’s half than any other Arsenal player (28).

It was a similar story in Arsenal’s previous trip to Manchester for December’s 2-2 draw at United: Guendouzi’s passing accuracy of 89 per cent was marginally surpassed by Torreira yet he attempted 11 more passes and six more in United’s half.

He has made 31 appearances in all competitions this season which, remarkably, is a tally only Torreira (32) surpasses.

There are, inevitably, improvements still to be made – he has a tendency to allow midfield runners to escape him, something that has been pointed out by coaches at London Colney – but his willingness to learn and improve is clear.

“He needs to work every day with ambition, as he is doing now,” said Emery. “Every training, every match, he shows his ambition and motivation to be an important player. It is the same for all players.

“It is a very short career and it need to use all the motivation for the best career, take a title and earn money for his family and future. He is showing us that.”

Guendouzi was one of the less heralded summer arrivals having played just eight top-flight games in his life but he already had a track record for changing opinion.

Paris Saint-Germain released the midfielder aged 14 but such was his progress with Lorient – even in relegation during the 2016-17 season – that Arsenal had to beat off competition from the Parisians to sign him last summer.

There were stories of a confrontational attitude but one of the reasons Guendouzi has earned so many admirers at Emirates Stadium this season is his willingness to carry the fight, to stand up to opponents in difficult circumstances.

He was one of the few to do that against City last weekend and is likely to do so again when Arsenal travel to Huddersfield Town on Saturday seeking their first Premier League away win since November 25.

Late last year, Guendouzi settled any doubt about his international future by pledging his allegiance to France amid interest from Morocco. Born in the Paris suburb of Poissy but with a Moroccan father, he is eligible for both nations but his decision last summer has not halted progress with Les Blues.

Guendouzi made his first France Under-21 appearances in November, after which he reiterated a desire to one day play with the France senior team.

“It is a dream for me to make it happen,” he said. If he continues on the current path, it will surely only be a matter of time.