In five innings before hostile crowds who consider his decision to leave South Africa an act of treason, he has carried the batting of his adopted country on his impressively broad shoulders. He has been deflected neither by the reaction of those who were once his compatriots, by having to overcome two broken bats in his last innings, nor by an unfeasibly garish hairstyle.
Were England to be playing a Test in a fortnight, the clamour for Pietersen's inclusion would be impossible to resist, even by the most conservative of selectors who might think that a flashy hairstyle is wearing Brylcreem. But the team are not on five-day duty again until May when they play Bangladesh.
After that come the Ashes. Nominally, Pietersen is behind two or three batsmen, but his entry to the scene has made his credentials obvious. He has not been fully accepted yet, but his style in this one-day series suggests it would not much matter if he had come from Mars to play for England.
Pietersen has scored 338 runs in five innings batting at No 5 in this series, including two centuries and a 50. His piece de resistance came in East London on Wednesday night when he scored England's fastest one- day century in 69 balls.
His biggest examination so far may be today at Kingsmead when England play the sixth and penultimate match in the series. He was born and went to school a few miles away in Pietermaritzburg and if he betrayed anywhere it could be said to be this place.
"I don't know what sort of reception I'm going to get, I've had nasty receptions the past two weeks," he said. "I don't have any regrets at all, I'm fulfilling a dream to play cricket for England. I like a challenge and when people are booing me and going ballistic I just take it on the chin."
Five years ago, Pietersen played here against England for KwaZulu/Natal. He scored 61 not out from 57 balls batting at No 9 and took 4 for 114 with his off-spin, including the wickets of Michael Atherton, Nasser Hussain and Michael Vaughan.
"I also had a long chat with Nasser and he helped me to make contacts with England," he said. A year later, Pietersen, the son of a South African father and English mother, was in Nottingham.
Perversely, he made as many enemies as friends the other night with his 69-ball century. When he hit the six to bring up three figures his first reaction was to clench his fists in celebration. But he stopped as if remembering that personal glory was not much good if the team had lost. Pietersen will provoke mixed reactions throughout his career, but the early probability is that England will do better with him than without him.