South Africa became the first side to top the ICC rankings in all three formats after Hashim Amla's stellar 150 propelled them to an 80-run win over England in the second one-day international at the Ageas Bowl.
On a day when the exiled Kevin Pietersen made 163 for Surrey, England were all out for 207, surrendering top spot in the ODI table just as they gave up their place at the Test summit earlier this month.
Amla began that Test series with an unbeaten triple century and he was on match-winning form again in Southampton, hitting 16 fours in a 124-ball knock that saw his side to a winning score of 287 for five.
The 29-year-old did need some luck, dropped by Craig Kieswetter on 42 and 92, but his 10th one-day hundred made him the fastest man to pass 3,000 runs in the format and it was an innings worthy of the status. England, though, will be sorely disappointed with their reply - with scores of 45 from Samit Patel and Ian Bell the best they managed.
Graeme Smith hit 52 for the tourists with Graeme Swann the pick of the England bowlers with two for 50.
Having watched Amla's masterclass, England made a terrible start to their reply, Alastair Cook losing his off stump to Lonwabo Tsotsobe off the second ball of the innings. Jonathan Trott contented himself with a supporting role and when Bell pulled his fourth boundary off Morne Morkel the pair had steered England to a promising 54 for one after 10 overs.
It took something special to hand Morkel South Africa's second wicket, debutant David Elgar clinging on to a stunning over-the-shoulder catch at fine-leg to see off Trott for 23.
The dismissal did not disrupt Bell's steady scoring and he was going nicely on 45 when Robin Peterson got one to straighten past the bat and into off stump. Peterson struck again in his next over, Ravi Bopara (16) planting a nothing ball straight to short cover to leave England rocking at 90 for four.
Kieswetter offered some relief by hoisting JP Duminy for the first six of the day in the 21st over but he did not last long. Elgar struck with his third ball in international cricket, Smith holding on at slip via a heavy deflection off De Villiers' gloves.
Eoin Morgan and Patel arrested the slide with a studious sixth-wicket stand of 41 before the Irishman fell to Duminy for 27. Wayne Parnell removed Tim Bresnan and Swann for ducks in the space of three balls and while Patel excited the fans with three fours and two sixes at the end, it was not enough to take England close.