A brilliant display with the ball and in the field preceded a nail-biting chase of 200 as the Northern Diamonds took a giant step towards the Rachael Heyhoe Flint Trophy knockout stages with a one-wicket victory over Lightning at Durham.

The Diamonds won their fourth game in a row - the last before the near seven-week break for the Hundred - with two balls remaining to start the seven fixture group stage in style, limiting the Lightning to 199 all out after they had been well placed at 120-1.

Jenny Gunn finished unbeaten on 41 off 77 balls, while Katie Levick hit the winning runs off Marie Kelly’s spin.

At the Seat Unique Riverside, spin was queen again, as has been the case for the Diamonds all season. Leigh Kasperek led the way with 3-39 from 10 overs. Hollie Armitage, Levick and Linsey Smith all claimed two wickets.

But the reply was not without significant drama as the Diamonds fell to 184-8 after 42 overs and 197-9 in the 48th, including the loss of opener Lauren Winfield-Hill for 61 off 75 balls.

It meant veteran Gunn, as she has so often done in the past, was left to steer the ship in order to secure the four points which goes a long way to securing the Diamonds a top three berth in the table.

The top three qualify for September’s knockouts, with the top placed team advancing directly to the final. The Diamonds are on 17 points, one behind Southern Vipers with them still to play.

Lightning fought incredibly hard on a slow pitch, tigerish with the ball and in the field just as the Diamonds had been. Spinners Kirstie Gordon, Josie Groves and Lucy Higham (3-50) shared seven wickets.

Earlier, Tammy Beaumont top-scored with 70 off 105 balls after Lightning had elected to bat, the England opener continuing an exceptional personal week.

Last Saturday, Beaumont was a surprise omission from the national team’s squad for the forthcoming Commonwealth Games, captain Heather Knight saying she lacked the aggression needed to help secure a gold medal in the T20 tournament.

But since then, she has posted scores of 119, 74 and this 70 playing fixtures for England, England A and the Lightning.

However, she fell in what turned out to be a crucial period of this fixture, the Lightning losing four wickets for one run in nine balls to slump from 153-2 in the 35th over to 154-6 in the 37th.

Kasperek had her lbw sweeping as the first of two wickets in the 37th, Bethan Ellis also trapped in front by the wily New Zealand overseas off-spinner.

Beaumont had earlier shared a 69 partnership in 14 overs with opening partner Marie Kelly, whose run-a-ball 37 displayed plenty to be entertained by. She used her feet well and danced down the pitch to loft left-arm spinner Smith over long-off for the first of three sixes in the innings.

The England linchpin also then added 51 for the second wicket with Sarah Bryce to leave the Lightning contemplating a total of 250 plus on a pitch used for Tuesday’s men’s ODI between England and South Africa.

However, the spinners were starting to squeeze. Only 10 overs of the 49.5 were sent down by seam from Beth Langston and Gunn, two players who are both returning from recent injuries.

There were multiple factors to this comeback with the ball and in the field.

The fielding was impressive after a couple of early minor errors and the bowling equally so.

The Diamonds raced through their overs to ratchet up the pressure on the Lightning batters, who just weren’t given any breathing space.

For example, Smith bowled one over in only 99 seconds and seamer Gunn sent another down lasting only two minutes, nine seconds.

Armitage claimed two wickets. She removed both of the Bryce sisters - Sarah caught and bowled in her first over and later Kathryn caught at cover to start the four-wicket, middle order collapse.

The skipper also led the side expertly, her field placing clever.

She was the conductor to this orchestra, and the all-rounder certainly extracted a harmonious and vibrant tune.

And there is now every chance of them being the headline act at the Lord’s final on September 25!

The Lightning were at least able to scrabble together a 200 target, with Higham hitting an entertaining 27 before being stumped off Levick with the first ball of the innings’ 50th over.

The Diamonds didn’t find their chase easy at all, even with Winfield-Hill making a third fifty in four RHFT innings - off 57 balls.

Smith was trapped lbw by left-arm swing bowler Grace Ballinger in the second over, leaving the score at 5-1, before Winfield-Hill and Armitage shared a busy 70 for the second wicket.

Armitage contributed 20 of those, while Winfield-Hill handsomely lofted the left-arm spin of Gordon over long-on for six.

Gordon, however, was to have an impact. She forced Armitage to play on in the 13th over - 75-2 - and when she trapped Sterre Kalis lbw for four, the Diamonds were 84-3 in the 15th.

By the time Winfield-Hill reached her latest half-century, the Diamonds were 94-3 in the 19th.

Academy graduate Phoebe Turner chipped a return catch to leg-spinner Groves, leaving the score 115-4 after 24.

And when Winfield-Hill slog swept Higham’s off-spin out to deep mid-wicket, the Lightning were right back in the hunt at 131-5 in the 27th over.

England A wicketkeeper bat Bess Heath then sliced Groves to backward point shortly afterwards - 142-6 after 30 - before Higham trapped Langston lbw to leave the Diamonds seven down in the 38th over and still needing 38.

Kasperek was then bowled by Higham at the end of the 42nd over - 184-8, with 16 needed.

Emma Marlow helped Gunn whittle that target down to three before edging Kelly to slip. The bowler then had two to defend off the last, only for Levick to drive a single through the covers and secure a crucial four points.

The Diamonds then celebrated in the dressing room by singing Jenny Gunn's name. It was a tune Armitage no doubt orchestrated!

Diamonds all-rounder Jenny Gunn said:

“Whoever won, it was a great game of cricket. To be on the winning side it is a brilliant feeling. It was certainly tense.

“It was a team performance all round, and it was great to be out there when Katie Levick hit the winning runs.

“We just need to keep winning. We’ve got a great balance of experience and youth, but it shows how they’re developing that they can come in and contribute in such a situation. Phoebe Turner did, Emma Marlow as well at the end. Tip and run was what was required.

“Lev said it was the most important run of her career!”