Brave 56-0published at 32 balls
But her second ball is crunched away for four by Danni Wyatt, who is looking in great form.
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Southern Brave win by 27 runs
Nat Sciver-Brunt makes 49 but Rockets can only reach 130-7
Brave made 157-6 with Mandhana making 55, Bouchier 31 and Wyatt 27
Spinners Smith takes 2-34 and Gordon 1-17
Opening game in 2023 Hundred
Southern Brave finished as runners-up in last year's women's competition
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Timothy Abraham and Ffion Wynne
But her second ball is crunched away for four by Danni Wyatt, who is looking in great form.
And now here is one of the most entertaining bowlers in the world.
Australia leg-spinner Alana King is on for the first time.
Michael Vaughan
Former England captain on BBC Test Match Special
I can't believe Danni Wyatt hadn't been picked before in a Test. We saw in the Ashes what she added in the middle of the Test, plenty of energy, great in the field.
Alexa Stonehouse is back for a second set of five after a tough start.
She's more consistent this time around, helped out by Jo Gardner who pulls off a fine bit of relay fielding on the boundary to save two runs.
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Shane: Hard to look past the Oval Invincibles again, kept the majority of their team and just strong in every facet.
Michael Vaughan
Former England captain on BBC Test Match Special
This is now a really good start for the Brave. If you get out of the powerplay on 40/45, especially without losing a wicket, it's a great start.
They started a little slowly, but this has turned into a solid start for Southern Brave as Danni Wyatt gets her first boundary, guided down to third as Sciver-Brunt bowls too wide.
That ends the powerplay, meaning Trent Rockets can now move some more fielders out to the boundary for protection.
Michael Vaughan
Former England captain on BBC Test Match Special
Pure timing, right in the slot, a wonderful strike.
Alison Mitchell
Cricket commentator on BBC Test Match Special
This one has gone a long way, this is where Mandhana is so dangerous. That's a huge six.
Oh, class!
Smriti Mandhana smashes one into the stands for the first six of The Hundred 2023!
Katherine Sciver-Brunt will not be pleased with that...
Michael Vaughan
Former England captain on BBC Test Match Special
If you can match shorter bowling with a pull shot, it can be very, very difficult to bowl to. That's a brilliant shot.
Make that two!
Much more controlled from Mandhana this time as she pulls firmly through the leg side for four more.
After a bit of a scratchy start, one of the world's best is away.
Tash Farrant
England bowler on BBC Test Match Special
Dattani just offered a little bit of width to Mandhana, she wasn't really in control of that. Even though it was streaky, hopefully it will get her up and running.
There's the first boundary!
Naomi Dattani starts well but bowls a little too wide to Smriti Mandhana, who slashes it away for four.
A tidy start for Sciver-Brunt, who ends the over with a short ball that pins her old team-mate Danni Wyatt in the ribs.
The pair have known each other for years and exchange a friendly laugh at the end - though I suspect Wyatt's was through gritted teeth!
Still no boundaries off the bat for Southern Brave...
Tash Farrant
England bowler on BBC Test Match Special
Knowing Katherine Sciver-Brunt, she will be nervous having retired from international cricket, but she will be keen to show she is still one of the best in the world.
And here is England legend Katherine Sciver-Brunt, who retired from international cricket earlier this year.
She hasn't played competitively for a while so she'll be well up for this challenge.
Tash Farrant
England bowler on BBC Test Match Special
I think it's a really good plan from Dattani to try and get it in to the ribs of Wyatt. She does not look comfortable there.
Another left-arm quick in Naomi Dattani, who played for London Spirit last year, will bowl the next five.
Her second ball is a wide - Rockets keeper Lizelle Lee has been diving all over the place here!
But Dattani corrects herself, causing Wyatt a bit of trouble with a short ball as Brave are just making the most of the wides at the moment.
Michael Vaughan
Former England captain on BBC Test Match Special
The batters in the first 25 balls have got that licence to try and get teams off to a strong start, with only two fielders allowed out of the circle.