Despite losing three wickets in the last three balls of their innings, Longford progressed to the TCL Boom grand final with a tie against Bracknell.
With Longford needing just one run to confirm their grand final berth with a win, Amy Buettel bowled Emily Scott before Nicole Davey was run out and Karlee Fulton was bowled - still sending the Tigers to the final.
Batting first, Bracknell made 5-104 as captain Cassie Walker top scored with 27 and Stacey Norton-Smith (2-5) and Karlee Humphries (2-14) bowled tight.
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Norton-Smith made 28 to get the Tigers off to a strong start in chase but no other batter made double figures, with Bracknell's 41 extras hurting them in the end.
Walker (2-9) and Buettel (2-14) were superb with the ball, giving Bracknell a shot at direct qualification.
They will have to wait till next week for their chance at securing a grand final berth as they face Trevallyn - who defeated ACL by 29 runs in the eliminator.
Batting first, Trevallyn made 3-138, steered by the prowess of Maxine Woods (25*), Tracey Miller (23*) and Heather Styles (25*).
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With resident power-hitter Narine Maurangi absent for ACL's biggest game, Sally Kershaw took the big-hitting responsibilities in chase - smacking 20 off 10 at number three before being run out - while Danielle Kelly retired on a composed 25.
Christina Kelly's 12 proved to be the next best score after her sister's retirement as Trevallyn starved ACL of runs - finishing on 6-109.
Trevallyn take on Bracknell next Sunday in the preliminary final.
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