England levelled the series in Durban on Friday night when they beat South Africa by 2 runs in the second T20I.
The result means it is all to play for in the third and final encounter on Sunday, which will be played at Supersport Park in Centurion.
Quinton de Kock won the toss and sent England in to bat first as Bjorn Fortuin came into the side in the place of Dale Steyn, who was rested.
The Proteas started well with the ball as they restricted England’s dangerous top order to fly out of the blocks, restricting the hosts to 90-3 after 10 overs with Jos Buttler, Jason Roy and Jonny Bairstow back in the hut.
But some big hitting by Ben Stokes and Moeen Ali in the latter stages of the innings saw England pass the 200-run mark to finish on 204-7 in their 20 overs.
Beuran Hendricks and Lungi Ngidi, especially took some battering towards the end as England responded well to their slow start.
De Kock and Temba Bavuma got the home-side’s run chase off to an excellent start, reaching 69-0 after 6 overs as the Powerplay came to an end.
The captain stormed to his half-century off only 17 deliveries , breaking his own record for the fastest half-century by a South African in T20Is.
De Kock was on a mission but mistimed a Mark Wood delivery and was caught by Ben Stokes on the boundary for 65 from 22 balls.
Wood then got rid of Bavuma as well for 39 as the Proteas reached 101-2 after 10 at the halfway mark of their innings.
David Miller came out and struck a few sixes but went for one too many when he hit a Stokes full-toss straight down Chris Jordan’s throat.
The dismissal of De Kock saw a big drop in the run-rate, though, and the Proteas began to fall behind as the innings wore on.
Jon-Jon Smuts failed to get going and was bowled around his legs by Jordan for 13.
Jordan clean bowled Andile Phehlukwayo with his very first delivery as England looked set for an easy victory.
Rassie van der Dussen hit a few boundaries towards the end but it wasn’t enough as Jordan bowled a brilliant penultimate over to restrict the Proteas.
But it all went down to final over as the Proteas required 15 runs from six balls and a six and a four by Dwaine Pretorius put South Africa back in the contest.
They needed 3 from the final two deliveries and Tom Curran made a valuable breakthrough by trapping Pretorius in front.
South Africa then required 3 from the final ball for victory or 2 to send the match into a Super Over.
But, Bjorn Fortuin tried to scoop Curran over short fine leg but it went straight into the hands of Adil Rashid as England won by 2 runs.
South Africa: Quinton de Kock (captain & wicketkeeper), Temba Bavuma, Rassie van der Dussen, JJ Smuts, David Miller, Dwaine Pretorius, Andile Phehlukwayo, Beuran Hendricks, Tabraiz Shamsi, Lungi Ngidi, Bjorn Fortuin
England: Jason Roy, Jos Buttler (wicketkeeper), Jonny Bairstow, Eoin Morgan (captain), Ben Stokes, Joe Denly, Moeen Ali, Tom Curran, Adil Rashid, Chris Jordan, Mark Wood
Photo: Dan Mullan/Getty Images