South Africa have earned a record-breaking victory over England in the second one-day international, chasing down 343 to prevail by five wickets.
Despite the pressure of needing to earn a whitewash series triumph to remain in the hunt for automatic qualification for the World Cup, the Proteas again impressed on Sunday, a century from Temba Bavuma putting his nation into an unassailable 2-0 lead in the best-of-three series.
Like on Friday, England lost the toss, but South Africa put the visitors into bat on this occasion, giving them a chance to post an imposing total.
Either side of Ben Duckett's dismissal for 20, Brook hit seven fours and four maximums during a 74-ball knock of 80, and his exit from the crease was not necessarily felt as Jos Buttler and Moeen Ali took over.
Moeen made 51 from 45, and while Chris Woakes (14) and Sam Curran (28) added valuable runs, it was Buttler's 94 from 82 which stood out, the skipper ending unbeaten with eight fours and three sixes to his name.
In making 342-7, England were the clear favourites to prevail with the highest-ever successful chase at this particular ground standing at just 274.
Nevertheless, South Africa never particularly found themselves at a disadvantage throughout their reply, which started with Quinton de Kock and Bavuma putting on 77 for the opening wicket.
Although the former went for 31, Bavuma was ably assisted by Rassie van der Dussen (38) before he departed for 109 off 102 balls, hitting 14 fours and one six.
To England's credit, they pegged South Africa back when it appeared that they would race to victory, but a boundary off the final ball of the penultimate over and a six off the first ball of the final earned South Africa the win with five deliveries remaining.