South Africa's batters held their nerve to deliver a surprise six-wicket victory over England at the women's T20 World Cup in Perth on Sunday.
The Proteas are making the early running in Group B along with the West Indies, who beat newcomers Thailand on Saturday. Only the top two from each of the two five-team groups qualify for the knockout phase.
Chasing a modest 124, South Africa appeared in control at 90 for 1 in the 16th over before the match turned with the wickets of captain Dane van Niekerk (46) and Marizanne Kapp (38) in quick succession.
Needing nine runs off the final over, Mignon du Preez was the hero with a six off the third ball of the final over from Katherine Brunt before then hitting the winning runs with a boundary.
"There was a lot of nerves, but I've played enough games in my career to step up in crucial moments and to do that is special," said Du Preez, who was playing in her 100th T20 international.
South Africa's triumph was just their fourth victory over England from 19 T20Is and has given them a perfect start to contend for a first title.
"There has been a few nightmares in the past (against England) but to finally put that behind us and to move forward is really exciting," du Preez said.
"We've kind of had a monkey on our back. This will give us a boost and we want to go a step further than the semi-finals and take the World Cup trophy home."
South Africa's impressive performance started as Van Niekerk's decision to bowl was vindicated when her accurate attack restricted England to 123 for eight off their 20 overs.
England had started positively through opener Amy Jones, who hit four boundaries in her first 13 balls faced before holing out in the fourth over.
They were then shackled by disciplined bowling until Natalie Sciver (50) upped the ante in the backend of the innings, but their total ultimately proved not enough.
Sciver said three-time finalists England would not panic despite being in an early hole.
"It puts the pressure on," she said. "A bit of pressure will hopefully see the best of us. Sometimes you have a few nerves around for the first game."
England will be hot favourites in their next game against Thailand in Canberra on Wednesday, while South Africa play the southeast Asian debutants on Friday.