He knows that complacency is the enemy of glory, and also that there is one crucial piece of the jigsaw missing in his scintillating side.

The City manager makes no secret of his desire to acquire a central defender to address the area of weakness in his squad – and some would say his first-choice team.

It is no coincidence, given the club’s burning ambition to win the Champions League, that all of Guardiola’s targets would be available for the knock-out rounds in Europe that start in February with a tie against Basel.

The defender he craves above all others, Leonardo Bonucci, will be the hardest to acquire. The Italian star made a surprise switch last summer from Juventus to AC Milan, partly because he was reluctant to move away from his homeland.

That move has gone more than a little sour, with Milan struggling this season, and rumours are rife that the 30-year-old might be tempted away. 

If so, City would face stiff competition from both Barcelona, looking to replace Javier Mascherano who is heading to the Chinese league, and Chelsea, managed by Bonucci’s former boss Antonio Conte.

The Italian’s excellence is undoubted. In a list of the 100 best players in the world published last week, Bonucci ranked second among central defenders behind only Sergio Ramos, of Real Madrid. 

Several major clubs are eager to snap up a centre-half in the January transfer window, and the eligibility for the Champions League of Virgil van Dijk, Inigo Martinez and Jonny Evans makes them prize targets.

Liverpool and Chelsea, as well as Manchester City, have been keeping a close watch on Southampton ace Van Dijk. The stumbling block could be the £60million fee reportedly being demanded by the Saints.

Arsenal have a strong interest in Evans, the West Brom defender Guardiola tried to bring in last summer. The former Manchester United player is also on the radar of his old club.

Another possibility is Spain international Martinez, a 26-year-old who has spent his entire club career at Real Sociedad.

His ability on the ball would suit the style of Guardiola, and the Spanish connection might suit the City boss.

The battle for all these players will be intense. What will make the difference?

All the clubs have money, so does City’s success and style give them an edge? Does the lure of playing for Pep Guardiola make a difference? It should mean a compelling few weeks of transfer speculation and accumulation.

Normally, it is about the contest to sign up star attackers who can score goals and bring fresh energy to a team. This winter high-class defenders are the rarities, as the 3-3 draw between Arsenal and Liverpool illustrated.

There are only four in the top 50 of those world rankings, and only 15 in the next 50. City’s best is left-back Benjamin Mendy, at No97, and he is sidelined with a long-term injury.

It is not merely desire from Guardiola to buy a defender. It is a burning necessity.