IF you are coming to Blackpool for Wednesday’s Charlotte Edwards Cup crunch clash between Thunder and the Northern Diamonds (11.30am), it’s probably worth remembering a few things. 

Put a pair of sunglasses in your bag, sun cream too alongside the sandwiches. 

But what could come in handy most of all is a calculator as the race for the two remaining places on offer at Finals Day on Saturday could get complicated.

The group-winning Blaze have already qualified directly for the final at New Road in Worcester, with two more places to be determined.

The Southern Vipers sit second in the table on 17 points ahead of the Diamonds (also on 17) courtesy of a superior net run-rate. Thunder are in fourth on 13 points, with Western Storm a point further back sat in fifth place. 

There are five points for all teams to play for, including a bonus point for a big win, and there is a scenario which would see all teams finish on 17 points and net run-rate decide the qualifiers.

Vipers host Sunrisers (7pm) and Storm host Blaze (2.30pm). 

To simplify things for Thunder, they have to win. No other result would qualify them. 

But if they don’t win with a bonus point - a victory with a scoring rate 1.25 times that of your opponents - then they also have to overturn a slightly inferior net run-rate.

A couple of examples of how they would do that are as follows. 

If Thunder (NRR - 0.064) score 140 batting first, they would have to restrict the Diamonds (0.162) to 134. If the Diamonds bat first and score 140, Thunder would have to win in 19.1 overs.

Putting aside the complexities, Thunder have a great chance having won three of their last four games, including against South East Stars at Blackpool yesterday when they fought back from the Stars being 87-0 chasing 166 to triumph by 16 runs.

“It was great to get over the line,” said captain Ellie Threlkeld, reflecting on a game in which Emma Lamb made 63 and was then one of five bowlers to take two wickets.

“It was a great team win, and everyone stood up when they needed to. That’s exactly what you want. I couldn’t be happier.

“We managed to drag it back really well in the second innings. I was pleased with the bowlers, and it was also a really good fielding performance.

“The outfield was really fast, so it was tough in the field. But the girls did a great job.

“There were also some standout contributions with the bat. Lamby was outstanding at the top, as she has been all year.

“The win’s going to build a lot of belief in the group. The girls are up and about, and I’m really confident about Wednesday. It’s another must win game for us, and the Lancashire v Yorkshire rivalry will make it even more special. I’m really looking to forward to it.”

Thunder’s upturn in form has come after losing their first two games in this competition added to a winless start from five Rachael Heyhoe Flint Trophy games.

“After a tough start in the 50-over comp, it’s been pleasing to get a few wins under our belt,” continued St Helens-born Threlkeld. 

“We’re doing a lot of things right and showing some signs of really good cricket. Hopefully we can build on this and keep progressing through the season.

“The games we’ve won, there’s been no secret to it other than doing all three disciplines really well. The England girls have also made a big difference.”

Lamb and Cross returned to the side against the Stars yesterday following an England training camp as they build up to the Ashes series later this month. Thunder will hope to add Sophie Ecclestone to their ranks on Wednesday.

“The nature of this competition now, everyone’s strong and teams are beating each other,” added Threlkeld. “It’s made the table pretty tight.

“For us, we’ve seen every game as a must win, not just this one (against the Diamonds).”

Having won their first four games of the competition, the Diamonds needed to win one of their remaining three games to qualify for Finals Day. 

They have wasted the first two chances, with defeats coming against Blaze and Southern Vipers at home on Friday and yesterday. Captain Hollie Armitage and company know a win will qualify them. 

This is the first part of a T20 double header with Lancashire’s men, who face Worcestershire in the Vitality Blast at 5pm.