Five goals in five games, plus one assist and three woodwork strikes is evidence that the Argentinian is as sharp as he’s ever been.
Kun celebrated his 30th birthday in the summer and, after a knee operation towards the end of last season, played for his country in the World Cup.
He claimed the operation allowed him to play free of pain for the first time in several years and the results were there for everyone to see as he scored both goals in City’s Community Shield win over Chelsea.
His first goal at Wembley was his 200th for the Club, having been stuck on 199 for several months.
His next goals came in the 6-1 win over Huddersfield Town – yet another Premier League hat-trick – before he thundered a couple of efforts against the woodwork away to Wolves.
But for a coat of paint, he could have been on eight goals already.
So, what are the targets he can reach this season?
Aguero has moved above Billy Meredith in the Club’s all-time League goal-scorers with 146 – he needs 12 more to draw level with Tom Johnson and Eric Brook and 13 to top the list.
If Kun can score another 29 Premier League goals this season, he will move into the top five all-time goal-scorers in Premier League history by drawing level with Thierry Henry on 175.
Just five more will elevate him from tenth to eighth and above a player he greatly admired - Michael Owen.
Another 17 would put him level with sixth-placed Robbie Fowler – one of four strikers in the top 10 to have played for the Blues (Frank Lampard and Andy Cole being the others).
He needs just three more appearances to complete 300 games for the Blues.
Two more Premier League hat-tricks would see him draw level with Alan Shearer’s 11, too – and would anyone bet against him getting some/most/all of the above?
After his return from his summer break, Pep Guardiola said of Sergio: “We were really impressed when he arrived. Sergio always has a little bit with his physicality… maybe he needs a little bit more time to take his physical condition. But he arrived so sharp, so good.
“I think at the end of last season, the knee operation. He suffered the previous years with a little bit of a problem and Ramon Cugat the best doctor in the world made the perfect surgery and now he feels free.
“I think it's good news for us for the season. He scored two goals, produced chances, he could have scored three or four or five. That is good. Him with Gabriel (Jesus), we have, in that position, good options.”
With Sergio not included in Argentina’s latest squad, the City talisman can rest up before the next round of matches.
A frightening thought for defences up and down the land…