Northern Diamonds 176 for 4 (Campbell 76, Kalis 41*) beat Central Sparks 175 for 7 (Fackrell 42*, Davies 42) by six wickets
A dominant bowling display preceded a comfortable chase of 176 as the Northern Diamonds booked their place in Saturday's Rachael Heyhoe Flint Trophy final with a semi-final eliminator win over Central Sparks at Scarborough.
The Diamonds will travel to Northampton to face defending champions Southern Vipers in a repeat of last season's final.
Beth Langston, Rachel Slater and Linsey Smith claimed two wickets before 42 apiece for Gwen Davies and Ria Fackrell recovered the Sparks from 68 for 5 to 175 for 7.
The Diamonds fell from 33 without loss to 42 for 3 in reply before aggressive Ami Campbell and more reserved Dutch international Sterre Kalis shared 116 for the fourth wicket, posting 76 off 78 balls and 42 not out respectively.
Campbell's half-century was her first of the season as the six-wicket win was secured with 17.1 overs remaining.
In-form Sparks captain Eve Jones elected to bat amidst morning dew and was one of three wickets to fall inside the opening 10 overs - 35 for 3 - after miscuing a cut at Slater's left-arm seam to point, falling for only nine.
Marie Kelly and Issy Wong were both trapped lbw for golden ducks, the latter as one of two wickets in three balls for left-arm spinner Smith in the 17th as the score fell to 68 for 5.
Davies and Fackrell both played in reserved fashion in their attempt to turn the tide. And while they managed to gain respectability, with the help of Emily Arlott's 29, it proved to be nowhere near enough against a Diamonds side whose only blemish in the first half of the game was a couple of late dropped catches.
Langston and Smith returned 2 for 29 and 2 for 25 from their 10 overs, though they were unable to break an eighth-wicket partnership of 74 between Fackrell and Arlott inside the last 19 overs of the visiting innings.
Captain Hollie Armitage, whose side has now reached all three finals in the regional era - they are still chasing a first trophy - then got the chase off to a flying start with five boundaries in her first nine balls. She made 25 off 16 before miscuing off-spinner Georgia Davis to mid-on, leaving the Diamonds at 33 for 1 in the sixth over.
Arlott then removed Rachel Hopkins and Leah Dobson to open the door for the Sparks. But it was quickly shut by Campbell and classy Kalis. The pair shared four sixes in their near 22-over alliance, Campbell with three of them down the ground or pulled. She reached her fifty off 51 balls and almost doubled her previous tally of competition runs this season before falling with victory all but secured.
"It just feels great to have come off the back of a fairly poor season for me and to do something good," Campbell said. "To get us over the line and into the final is superb.
"I felt very nervous when I went in. I knew I had to stay there and was quite defensive at the start. That's not my usual game, but it's something I'm getting better at and am working on.
"We want to beat the Vipers, especially after losing to them the other day. That was really disappointing. But we have been playing some good cricket and have a lot of momentum going into the final."