England, after early losses to Australia, the West Indies and South Africa, steadily improved and, playing knockout cricket through their last five matches, turned the corner with wins over host New Zealand and India which clinched a semifinal spot.
Still, they needed to topple South Africa and Wyatt helped them do that, with the assistance of the South Africa fielders who dropped her five times, at 22, 36, 77, 116 and 118. Wyatt wasn't used as an opener at the start of the tournament but was forced into that role and came into her own at Hagley Oval.
South Africa's bowlers either were too full or too short and Wyatt revelled in the opportunities the errant length and width provided. She hit powerfully through the offside forward of point and rifled short balls to the boundary behind square.
"My plan was to capitalise on any width and run well between the wickets, just play my game," Wyatt said. "There have been a few good catches taken off me in the tournament. It was nice to have a few dropped today."
England lost opener Tammy Beaumont in the fourth over but Wyatt held together the innings and built partnerships whenever possible. The best produced 116 runs for the fifth wicket with Sophia Dunkley, who made 60 from 72 balls.
Wyatt finally was out in the 45th over but England's total was made more substantial by Ecclestone, who hit 24 runs from 11 balls before falling to the last ball of the innings.
Shrubsole then knocked off the top of the South Africa innings when she dismissed Wolvaardt and Lizelle Lee within the first four overs.
Ecclestone then produced an outstanding performance to ensure South Africa had no chance of recovering, living up to her billing as the No 1-ranked bowler in women's one-day internationals.
"Sophie has been brilliant for us," England captain Heather Knight said. "That's her first five-for in international cricket and I thought she bowled outstandingly. She and Charlie Dean were really good on a wicket which had a little bit in it for them."
Knight said England would start as long shots again in the final against Australia on Sunday.
"I think we're going in as underdogs for sure but it's a fresh slate isn't it?" she said. "It's a fresh slate on the morning of the game and what a story will be written for us if we can do it."