Five South African bowlers claimed wickets to bundle out the West Indies for just 153, before a simple chase in Antigua.
A dominant performance with both bat and ball has given the tourists an early lead in their five-match ODI series.
Three bowlers claimed multiple wickets for the tourists, as the West Indies slumped from 70/2 to 153 all out inside 47 overs.
In response, Lizelle Lee's 21st ODI fifty led the charge, with the opener and Dane van Niekerk guiding South Africa to an eight-wicket win.
A clinical performance with the ball before a classy knock from Lizelle Lee has powered South Africa to an early series lead against West Indies 👏#WIvSA | https://t.co/VWfa4h03Eu https://t.co/Jtr2XFWdjw— ICC (@ICC) September 8, 2021
West Indies won the toss and elected to bat, with openers Hayley Matthews and Kyshona Knight circumspect in a start of 6/0 in the first five overs.
Knight (5) was bowled by Marizanne Kapp (1/22) at the end of next over, and Tumi Sekhukhune (2/32) soon joined in to claim Matthews (4) in her first over.
At 12/2 after the first 10 overs, Britney Cooper and Deandra Dottin sought to lift the tempo, though South Africa kept the hosts to 28/2 at the 15-over mark.
Dottin relieved the pressure with four boundaries off a Sekhukhune over to up the run rate, though the earlier pressure played on the hosts, with Dottin falling to the spin of Sune Luus (1/40) for 38. Against a ball flighted outside the off stump, Dottin mistimed her slash to find Mignon du Preez.
The problems for the hosts were compounded by Britney Cooper having to retire hurt, as South Africa continued to tighten the screws. Despite the wickets in hand, the miserly bowling earlier heaped pressure on the West Indies middle order, who were unable to accelerate.
Kycia Knight's 39 showed some resistance to the the South African bowling barrage, though the 'keeper for the hosts failed to build a partnership with wickets tumbling at the other end.
Chedean Nation (5), Chinelle Henry (4) and Anisa Mohammed (1) fell as Ayabonga Khaka (2/17) and van Niekerk (2/23) moved South Africa further ahead. Knight was run out by du Preez in perhaps the biggest indication of the unrelenting pressure, as the West Indies were bowled out for 153 in the 47th over.
Lee and Laura Wolvaardt quashed any early talk of a West Indian comeback, putting on 88 for the first wicket inside 22 overs.
Wolvaardt (36) was clean bowled by a peach from Mohammed, and South African wobbles were present after Luus fell eight balls to Qiana Joseph for a duck, adjudged lbw.
In spite of the double blow, South Africa pushed on through Lee and van Niekerk, with the opener finishing on 91* from 127 balls.
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