Southern Vipers all out for 231 after being put in by Lauren Winfield-Hill
Georgia Adams top scores with 80, reaching 500 Trophy runs
Northern Diamonds all out for 193 in 42,2 overs
Sterre Kalis makes 55, her third successive half century
Charlotte Taylor takes 6-34 from her 10 overs for Vipers
Southern Vipers also won every game in group stage
Adams 58, Bouchier 0
Jenny Gunn starts a new over and Georgia Adams collects a single.
New batter Maia Bouchier is on strike. She produces a couple of plesant-looking drives but they are straight to fielders.
That's the halfway point of the innings.
McCaughan c Heath b L Smith 35 (Vipers 100-1)
Finally! Linsey Smith outfoxes 18-year-old Ella McCaughan who feathers one to keeper Bess Heath.
The Diamonds have their voices back in the field.
Maia Bouchier is the new woman in. Time to build some dots.
Adams 55, McCaughan 37
A couples of quick singles and that's the 100 up for the Vipers....it's the fourth three-figure opening partnership they have produced in this competition.
Adams 55, McCaughan 34
I've been super impressed with Jenny Gunn's aggression and variations.
She's asking all sorts of questions of the batters. It's just a shame she's come into the attack when both players at the crease are set.
Still no closer to a wicket.
Adams 53, McCaughan 33
I think Alex has got it spot on (see 11.42 entry), Vipers are in total control of this match.
Another over, four runs are added.
The Diamonds need this partnership broken.
Tweet us at #bbccricket
What have you made of the Rachael Heyhoe Flint Trophy? Should it become a permanent part of the domestic women;'s cricket calendar? Should Georgia Adams be called up by England? Send us your views on these and any other issues of your choosing?
Adams 52, McCaughan 30
Another good over from Jenny Gunn. No theatrics just very economical bowling.
Looking into the Vipers' opening partnership, this pair have been the foundation of the side's six wins out of six in the group stages.
First-wicket stands of 111, 105, 84, 10, 155, 52 and now 90*.
Alex Hartley
England spinner on BBC Radio 5 live Sports Extra
Quote MessageIt's just easy for the Vipers at the moment. If I was in this situation I'd bring some catchers in and try to put some pressure on."
Adams 51, McCaughan 29
Linsey Smith comes back into the attack.
You sense a switch has been flipped for the Vipers now. Ella McCaughan adds another four, six from the over.
What a brilliant opening partnership this has been, The Northern Diamonds desperately need a wicket.
Vipers 82-0
A fantastic 68-ball 50 from Georgia Adams.
A single on the off-side takes her to a fourth half century of the campaign.
So far she's struck 37, 55, 44, 89, 154*, 41 and now 50* this summer.
Sensational form.
Adams 48, McCaughan 22
Image source, Getty ImagesShot!
Ella McCaughan has been playing second fiddle to Adams for long periods of this innings.
Now she starts to up the gears, moving across and opening up the legside for two brilliant boundaries.
Nine from that over.
Adams 47, McCaughan 14
Georgia Adams has been incredible this summer. She's the leading run scorer in this competition for a reason!
Another good over from Jenny Gunn, three from it.
Isabelle Westbury
Ex-Middlesex captain on BBC Radio 5 live Sports Extra
Quote MessageAdams is now 45 not out. She looks like she's timing it gloriously."
Adams 45, McCaughan 13
Image source, Rex FeaturesAnd Phoebe Graham backs up her bowling partner with six fine deliveries. Again only one from the over.
Something's gotta give...
Adams 44, McCaughan 13
The Northern Diamonds turn to former England international Jenny Gunn.
Eleven tests, 144 ODIs, 104 T20s, you can't get much more experience than that.
Only a single off her first over.
Adams 43, McCaughan 13
Ella McCaughan grabs her second boundary off the final ball of Phoebe Graham's over.
That'll do her a world of good, she was just stalling slightly with Adams clocking up most of the runs.
If you haven't already spotted it, there is ball-by-ball radio coverage available at the top of the page from BBC Radio 5 live Sports Extra and BBC Radio Solent. Click the commentary link of your choice to tune in.
Adams 43, McCaughan 8
Georgia Adams is continuing her fine form and hits Katie Levick for three fours off the 13th over.
That'll bring up the Southern Vipers' 50. Adams is just seven away from another half century.
Adams 31, McCaughan 8
Phoebe Graham returns and this time it's Ella McCaughan who goes onto the attack.
A lovely, late cut adds another three down to third man.
Adams 28, McCaughan 7
Image source, Getty ImagesSpinner Katie Levick comes into the attack.
Georgia Adams immediately smashes her for four, but Levick recovers and finishes her set well.
Adams' lowest score in the Rachael Heyhoe-Flint Trophy is 37 - her best is 154 not out.