Riyad Mahrez goes from luxury to necessity: Richard Buxton
Man City attacker Mahrez should now be the first name on Guardiola's team sheet
Riyad Mahrez was once in danger of being an ostentatious luxury player at the Etihad Stadium.
Like a sparkly diamond ring bought on impulse, he was capable of catching the eye, but perhaps not the most productive of purchases.
Signed from Leicester City in July 2018 for £60 million (S$101.7m) on the back of his irrepressible role in the Foxes' unlikely title triumph, much was expected of the Algerian.
But early on, there were worrying signs that he might be best suited to being a big fish in a small pond.
Twelve goals in all competitions in his debut season in Manchester was a healthy haul, but Mahrez was firmly in the shadows of fellow wide attackers Raheem Sterling and Leroy Sane.
Not any more.
The Citizens' 3-1 win over Everton yesterday morning (Singapore time) was another example of how vital the 28-year-old has become to Pep Guardiola's team as they look to reclaim their English Premier League crown for a second time.
After Dominic Calvert-Lewin had cancelled out Gabriel Jesus' opener, Mahrez restored their lead from a free-kick, taking his direct involvement in City's goals to 17 from as many starts in all competitions.
He has scored seven goals and bagged 10 assists, including four goals and five assists in his last seven matches for the EPL champions.
Both City and Mahrez could have racked up even more impressive numbers had Ilkay Guendogan not left his shooting boots on the team bus.
Sterling, who scored the third goal and Jesus, too, were guilty of wasting chances laid on from the former Foxes winger, with their hesitant and hasty finishes.
It was not the first time that Mahrez has shown his worth.
His goals against Tottenham Hotspur, Watford and Bournemouth were the difference between edging out Liverpool to the title by one point and falling to the five-point gulf that currently exists between them.
Yet he has always been forced to play second fiddle to others in City's all-star cast.
Guardiola's continual plea for patience from the 28-year-old has underlined those frustrations.
The tables, however, have now turned, especially with a number of his teammates appearing as off-colour at Goodison Park as the luminous away kit they wore.
Scoring a late goal failed to mask Sterling's below-par display while Kevin de Bruyne's usual killer instinct had dimmed.
If they are to see off the domestic threat from Anfield for a second year running, it should now be Mahrez, rather than Bernardo Silva, that occupies the focal point of Guardiola's "him and 10 others" ideology on team selections.
On current form, no one else even comes close.
Few boast the contrasting experiences of winning the EPL title that he can.
At the King Power and Etihad Stadiums, Mahrez has done it as both an underdog and an overlord.
That diversity of success can serve City well in other potential banana-skin fixtures over the coming months.
Knowing how to win games is as much about personnel as it is tactics.
Liverpool's new-found gamesmanship, pioneered by Juergen Klopp and his backroom staff, is a perfect case in point.
Guardiola still refuses to stray from his pursuit of footballing purism - he doesn't need to.
In Mahrez, the City manager has the perfect antidote to resist any urges for compromise.