Northern Diamonds cruised to a six-wicket win over Central Sparks in the Rachael Heyhoe Flint Trophy play-off to set up a final against Southern Vipers.
Sparks were restricted to 175-7 in their 50 overs with Gwen Davies and Ria Fackrell both top scoring with 42.
Fackrell and Emily Arlott helped Sparks recover from 101-7 but struggled to accelerate against some tight bowling.
Ami Campbell's 76 off 78 deliveries helped Northern Diamonds reach 176-4 in just 32.5 overs.
Diamonds were wobbling on 42-3 at Scarborough after Arlott picked up two wickets in an over, but Campbell's fourth-wicket stand of 116 with Sterre Kalis (41 not out) paved the way for victory.
The final, a repeat of last year's showpiece, takes place at Northampton's Wantage Road on Saturday at 10:30 BST.
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