IRELAND will play Scotland for a place in the World T20 finals after another match winning performance by captain Isobel Joyce in Bangkok saw her side defeat Zimbabwe by seven wickets to complete a clean sweep of qualifying Group B.

Joyce, who starred with the bat against China on Sunday, showed the other side of her game with four overs of left-arm spin that returned figures of 4-20 and knocked the stuffing out of the Zimbabwe top order. She was again named Player of the Match.

In the afternoon heat, her teammates stuck doggedly to their task as well. Opening bowler Kim Garth led the way with 1-12 from her four overs, leggie Ciara Metcalfe took 1-13 from her set, Lucy O'Reilly claimed 1-7 and Robyn Lewis chipped in with two tailenders as the Africans were bowled out for 78.

A 48-run opening partnership between Cecelia Joyce and Clare Shillington then settled any remaining nerves and Ireland eased home with 28 balls to spare.

"It was a pretty comprehensive win," said captain Joyce. "We were delighted to keep them down to 78 after not taking a wicket in the first eight overs. The girls all bowled well, particularly Lucy O'Reilly who has been unbelievable through the three games. She's my go-to when we're in any trouble - and old head on really young shoulders."

While Ireland had already qualified for tomorrow's do-or-die deciders, the win was important because it meant avoiding tournament favourites Bangladesh, who also boasted a 100 per cent record in topping Group A.

"The game against Scotland is really more important than Saturday's final," Joyce added. "That's the game that decides who goes to India next year and it's going to be massive."

Ireland will be expected to beat Scotland, who have never been to a world finals, but the game has echoes of the 1997 play-off for the last place at the men's World Cup when Alan Lewis, father of two teenagers in the current squad, was on the losing side in Kuala Lumpur.