Marizanne Kapp hit a 27-ball 34 to hold her nerve as Oval Invincibles claimed a tense five-wicket win over Trent Rockets.
Rockets captain Nat Sciver's 59 off 48 balls got her side to 112-8 but she lacked support from her team-mates.
Invincibles skipper Suzi Bates top scored with 41 off 32 balls as she and rising star Alice Capsey, who made 24 off 18, got their side within striking distance before Rockets leg-spinner Alana King bowled 10 dot balls in a row to take the game deep.
With five needed from 10 balls, Mady Villiers and Kira Chathli crumbled against Bryony Smith, who took 3-21, but with two runs needed off two balls Kapp smoked a four to secure victory before roaring in celebration.
Here's also what happened:
The quirkiest moment of the game came when Alice Capsey spilled a caught-and-bowled chance off Sciver's bat into the stumps at the non-striker's end to run out Katherine Brunt. Brunt - who is married to Sciver - furiously whacked her bat into the ground, Capsey covered her mouth giggling while Sciver sheepishly winced.
Eva Gray bowled tightly for the Invicibles to finish with 2-17 including the key wicket of South Africa batter Mignon du Preez.
In the Invincibles innings England batter Capsey twice ramped a feisty Brunt and hit Sarah Glenn (2-29) for six down the ground in a dazzling knock as she and Bates put on 47 for the second wicket.
What's next?
Trent Rockets welcome winless London Spirit to Nottingham on Saturday (15:30 BST).
Oval Invicibles are not in action again until next Tuesday when they host high-flying Birmingham Phoenix (15:00).
Tomorrow's match sees unbeaten Southern Brave play Manchester Originals at the Ageas Bowl (15:30)
Post update
Post update
Oval Invincibles have now won two of their three group games, while Trent Rockets have lost two of their three.
The women are only playing six group games this year because of the delayed start with the Commonwealth Games.
Oval Invincibles captain Suzie Bates: "Marizanne Kapp was outstanding for us. It probably got a bit closer than we wanted it to but the way we started with the bat helped us soak up some of the pressure in the middle.
"I felt pretty good, I had to try and keep the momentum going after the first 25 balls. But the way Alice Capsey plays makes my job a lot easier!
"I just want her to keep playing on instincts and being brave so I try not to say too much to her!
"The pitch was a bit skiddy and it didn't look like it was coming on nicely but I'm really pleased with how our bowlers performed, we did well to make it difficult for Nat Sciver in the middle.
"It's nice to captain a new team, I'm loving it at the moment."
Post update
Kevin Howells
BBC Radio commentator
Trent Rockets supporters were disappointed with that. Will the men's team give them something to cheer for later on?
Post update
Issy Wong
Birmingham Phoenix & England bowler on BBC Radio
A low-scoring thriller! We saw some exceptional bowling from both ends.
Post update
Kevin Howells
BBC Radio commentator
A cracking game of Hundred cricket. They did it the hard way, but they will be giving themselves confidence heading into the next games.
BreakingInvincibles win by five wickets
Class from Marizanne Kapp!
The South Africa all-rounder gets down on one knee and slog-sweeps away to the boundary for four.
Pressure? What pressure?
There are some boos from the Trent Bridge crowd. They really wanted a Rockets win.
Invincibles 111-5
Win predictor has it 66-34% in Invincibles' favour.
Invincibles 111-5
Kirstie White gets a single.
Marizanne Kapp is back on strike.
Two runs needed from two balls.
There are no Super Overs/Super Sets or whatever you want to call them at this stage of the tournament.
WICKET
Chathli b Smith 0 (Invincibles 110-5)
Oh my days!
Kira Chathli looks to sweep away but an under edge goes through her legs and into middle stump.
Invincibles need three from three balls. Marizanne Kapp is fuming at the non-striker's end.
Not out
Oh it is so, so close. Such a marginal call but Martin Saggers decides that Kira Chathli just about gets her foot back over the line.
Third umpire
Has Kira Chathli been stumped?
Bryony Smith throws it wide and Chathli comes forward and seems to lose her balance.
It's close.
Invincibles 110-4
Need three from five balls
Oooh!
Bryony Smith bowls two dot balls to Kira Chathli.
What is going on? Invincibles need three from the final five balls and Smith is going to continue.
WICKET
Villiers c Glenn b Smith 6 (Invincibles 110-4)
Surely too late!
Mady Villiers looks to win it style but skies it straight up and Sarah Glenn takes a relatively simple catch.
With just three needed to win, surely this is over?
Post update
BBC SportCopyright: BBC Sport
Post update
Issy Wong
Birmingham Phoenix & England bowler on BBC Radio
That's the experience Kapp brings into the chase.
Post update
Kevin Howells
BBC Radio commentator
The Oval Invincibles are looking really strong now. As quickly as it seemed like it was weighing up equally, it's all gone now.
Invincibles 108-3
Need five from 10 balls
Nat Sciver finishes the set with two dot balls but it feels like it is going to be irrelevant and the game is already gone with those back-to-back boundaries.
Invincibles 108-3
Need five from 12 balls
Oh, that is definitely the game. Surely?
Nat Sciver goes a bit fuller and Marizanne Kapp plays the most glorious straight drive for four.
Live Reporting
Ffion Wynne, Callum Matthews and Timothy Abraham
All times stated are UK
Getty ImagesCopyright: Getty Images -
The quirkiest moment of the game came when Alice Capsey spilled a caught-and-bowled chance off Sciver's bat into the stumps at the non-striker's end to run out Katherine Brunt. Brunt - who is married to Sciver - furiously whacked her bat into the ground, Capsey covered her mouth giggling while Sciver sheepishly winced.
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Eva Gray bowled tightly for the Invicibles to finish with 2-17 including the key wicket of South Africa batter Mignon du Preez.
-
In the Invincibles innings England batter Capsey twice ramped a feisty Brunt and hit Sarah Glenn (2-29) for six down the ground in a dazzling knock as she and Bates put on 47 for the second wicket.
BBC SportCopyright: BBC Sport 
Latest PostKapp stays cool as Invincibles win
Marizanne Kapp hit a 27-ball 34 to hold her nerve as Oval Invincibles claimed a tense five-wicket win over Trent Rockets.
Rockets captain Nat Sciver's 59 off 48 balls got her side to 112-8 but she lacked support from her team-mates.
Invincibles skipper Suzi Bates top scored with 41 off 32 balls as she and rising star Alice Capsey, who made 24 off 18, got their side within striking distance before Rockets leg-spinner Alana King bowled 10 dot balls in a row to take the game deep.
With five needed from 10 balls, Mady Villiers and Kira Chathli crumbled against Bryony Smith, who took 3-21, but with two runs needed off two balls Kapp smoked a four to secure victory before roaring in celebration.
Here's also what happened:
What's next?
Trent Rockets welcome winless London Spirit to Nottingham on Saturday (15:30 BST).
Oval Invicibles are not in action again until next Tuesday when they host high-flying Birmingham Phoenix (15:00).
Tomorrow's match sees unbeaten Southern Brave play Manchester Originals at the Ageas Bowl (15:30)
Post update
Post update
Oval Invincibles have now won two of their three group games, while Trent Rockets have lost two of their three.
The women are only playing six group games this year because of the delayed start with the Commonwealth Games.
The women's table is starting to take shape now.
Post update
Oval Invincibles captain Suzie Bates: "Marizanne Kapp was outstanding for us. It probably got a bit closer than we wanted it to but the way we started with the bat helped us soak up some of the pressure in the middle.
"I felt pretty good, I had to try and keep the momentum going after the first 25 balls. But the way Alice Capsey plays makes my job a lot easier!
"I just want her to keep playing on instincts and being brave so I try not to say too much to her!
"The pitch was a bit skiddy and it didn't look like it was coming on nicely but I'm really pleased with how our bowlers performed, we did well to make it difficult for Nat Sciver in the middle.
"It's nice to captain a new team, I'm loving it at the moment."
Post update
Kevin Howells
BBC Radio commentator
Trent Rockets supporters were disappointed with that. Will the men's team give them something to cheer for later on?
Post update
Issy Wong
Birmingham Phoenix & England bowler on BBC Radio
A low-scoring thriller! We saw some exceptional bowling from both ends.
Post update
Kevin Howells
BBC Radio commentator
A cracking game of Hundred cricket. They did it the hard way, but they will be giving themselves confidence heading into the next games.
BreakingInvincibles win by five wickets
Class from Marizanne Kapp!
The South Africa all-rounder gets down on one knee and slog-sweeps away to the boundary for four.
Pressure? What pressure?
There are some boos from the Trent Bridge crowd. They really wanted a Rockets win.
Invincibles 111-5
Win predictor has it 66-34% in Invincibles' favour.
Invincibles 111-5
Kirstie White gets a single.
Marizanne Kapp is back on strike.
Two runs needed from two balls.
There are no Super Overs/Super Sets or whatever you want to call them at this stage of the tournament.
WICKET
Chathli b Smith 0 (Invincibles 110-5)
Oh my days!
Kira Chathli looks to sweep away but an under edge goes through her legs and into middle stump.
Invincibles need three from three balls. Marizanne Kapp is fuming at the non-striker's end.
Not out
Oh it is so, so close. Such a marginal call but Martin Saggers decides that Kira Chathli just about gets her foot back over the line.
Third umpire
Has Kira Chathli been stumped?
Bryony Smith throws it wide and Chathli comes forward and seems to lose her balance.
It's close.
Invincibles 110-4
Need three from five balls
Oooh!
Bryony Smith bowls two dot balls to Kira Chathli.
What is going on? Invincibles need three from the final five balls and Smith is going to continue.
WICKET
Villiers c Glenn b Smith 6 (Invincibles 110-4)
Surely too late!
Mady Villiers looks to win it style but skies it straight up and Sarah Glenn takes a relatively simple catch.
With just three needed to win, surely this is over?
Post update
Post update
Issy Wong
Birmingham Phoenix & England bowler on BBC Radio
That's the experience Kapp brings into the chase.
Post update
Kevin Howells
BBC Radio commentator
The Oval Invincibles are looking really strong now. As quickly as it seemed like it was weighing up equally, it's all gone now.
Invincibles 108-3
Need five from 10 balls
Nat Sciver finishes the set with two dot balls but it feels like it is going to be irrelevant and the game is already gone with those back-to-back boundaries.
Invincibles 108-3
Need five from 12 balls
Oh, that is definitely the game. Surely?
Nat Sciver goes a bit fuller and Marizanne Kapp plays the most glorious straight drive for four.
Definitely a shot of the game contender.