The overtures started around February time, when Manchester City had announced that Pep Guardiola would become their new manager at the end of the season. Guardiola wanted a full-back with searing pace and attacking instincts, somebody to build the play out from the back, and he wanted Héctor Bellerín of Arsenal.

To Guardiola, it was the perfect fit – a young player with Barcelona DNA and an education in the Premier League. These days, there is little doubt that, at only 21, the former Barcelona youth-team player is the finest right-back in England. Bellerín was named in last season’s PFA Team of the Year and this month he was shortlisted for the Fifpro World Team of the Year, alongside only one other Premier League defender – Chelsea’s David Luiz. The team will be announced in January.

And so City began Operation Bellerín. They opened talks with his people and sought to sell the merits of the move from a playing perspective. Above all, they made it clear they would be able to offer him a massive salary – far in excess of anything Arsenal would grant him. The transfer fee would not be a problem. The message from City was that they were prepared to pay whatever it took.

Other clubs were interested in Bellerín, including Barcelona, Manchester United and Atlético Madrid. But City were the most persistent. By far. They refused to take no for an answer. And they had the cash to be extremely persuasive.

The way many major transfers work is that the interested club plug away through intermediaries, outlining what they can offer and, once the player is keen, they go in through the front door with an official bid to his employer. It never got to that point with City and Arsenal over Bellerín.

Arsenal had got wind of things and their stance was resolute: Bellerín would not be for sale at any price. Arsène Wenger joked on Friday morning that City were “good clients”, having previously taken Emmanuel Adebayor, Kolo Touré, Samir Nasri, Gaël Clichy and Bacary Sagna from him. But, he added, those days were over.

“Today, we can give financial satisfaction and support ambitions and values that can make the players happy at this club,” Wenger said, as he prepared for his team’s trip to City on Sunday. “Before, due to the Emirates Stadium build, perhaps the financial gap was too big a difference to keep our players. We could not compete. We had to sell players.”

It was Bellerín who said no to City and the riches on offer, because he wanted to stay at Arsenal. In November he signed a six-and-a-half-year contract, worth £115,000 a week but, the Guardian understands, he could have got substantially more at City.

Bellerín stayed for a number of reasons, including a slightly unusual one in 21st-century football – the sense of loyalty that he feels towards Wenger and the club. He has not forgotten how the manager stood by him after his disastrous full debut in the Champions League defeat at Borussia Dortmund in September 2014 and his poor performance in the loss at Stoke City in December of that year.

Moreover, Bellerín considered how a number of former Arsenal players had fared since their departures. He thought about Clichy, Sagna and Nasri – together with Cesc Fàbregas and Alex Song. Has the grass been greener for the first three at City? Did Fàbregas’s dream return to Barcelona really work out? Song also went to Camp Nou, and he did not enjoy regular football.

“You can understand why City tried to sign Héctor over the summer because he has developed into a superb talent,” said Terry Burton, who was the head of coaching at Arsenal between 2012-14, where he worked with Bellerín. “I’m sure he will continue to be a target for clubs of Arsenal’s standing. There’s not many better right-backs around to have.

“Am I surprised that he turned down more money from City to stay at Arsenal? In the general climate, yes. But in Héctor’s case, no. He’s an intelligent player and he understands that if he continues to be the best right-back in the Premier League, Arsenal will reward him again in the next contract. He is sensible enough to realise that he’s on fantastic wages for a 21-year-old and further rewards will come with continued success.

“Héctor feels loved at Arsenal and I think he’s one of those that does need to feel loved. He’s built a lot of good relationships at the club and Arsenal are hardly the worst one in the world to be playing for. He’s made some good decisions. One was signing for Arsenal when he did, as a 16-year-old in 2011, and another has been staying with them now.”

Burton, the head of emerging talent at Southampton, remembers the time when Bellerín’s decision-making was not quite as sound. He talks about the concept of risk and reward, which has long been central to his coaching – in other words, when and where it is worthwhile to take a risk.

“We fell out after a NextGen European youth game in Marseille [in October 2012],” Burton said. “We needed a draw and it was 0-0 in injury-time. Héctor tried to nutmeg somebody just outside of his defensive third and they broke away to score the winner. I gave him a rocket, which he took. He’s a great lad and he’s got a really great attitude. It was an important learning situation, where you can hammer home the point. Young players have to learn game management.”

Bellerín’s pace and determination to attack were marked when he arrived at Arsenal from Barcelona; he was a winger at the time. But the club saw that he could be converted into a right-back, and they worked hard on the defensive side of his game.

“Could he defend the back post?” Burton said. “Was his body shape right? Was he aware of people coming in on him? Could he back in and jump and defend at the back post. With his pace, could he get out and close people down in wide areas and block crosses? But it was also in possession, and in terms of turnovers. He took a lot of chances in defensive areas. It was that decision-making, because he did turn the ball over quite a bit in his defensive third. He needed the awareness that his first pass, in certain areas, had to be a safe one.”

Bellerín has come to tick all the boxes – the speed of his development has been astonishing – and, having committed to Arsenal, he has emerged as a symbol of Wenger’s latest project. Bellerín has talked of Arsenal feeling like “home” and how signing the new contract “was the right thing for me to do”. He believes Arsenal are getting stronger each year and closer to the title. City will watch him on Sunday with a degree of regret.