Jake Ball, an England international of yore, takes the next five, and is also pretty much on the money.
Roy has a slight alarm as inside edge squirts past leg stump, but he still gets two from it.
Invincibles 5-0
Will Jacks takes two to one of the longer boundaries in Cardiff and then gets into a tangle, almost deflecting the ball down onto the stumps.
Very short straight at this ground, but Payne has not allowed the batters to take a swing yet.
Invincibles 1-0
And it's a wide first up, and off the first legitimate ball Roy pushes to leg for a single.
Post update
Welsh Fire are taking their positions while Jason Roy and Will Jacks emerge through the fire and smoke to stride to the middle.
It's a lovely day in Cardiff too, in fact it's a scorcher!
David Payne is all set to get it going to Jason Roy, here we go.
Get Involved
#bbccricket or text to 81111 (UK only)
We want to hear from you, so don't hesitate to get in touch via #bbccricket or text to 81111 - and don't forget to include your name if texting.
Today's key match-up
Two versatile young stars could be a fascinating match-up today.
Sam Curran is a real threat with the bat, but he could test Tom Banton with ball in hand as the talented batter could be one of Welsh Fire's key players with Jonny Bairstow having left the squad.
BBC SportCopyright: BBC Sport
Can Roy return to form?
Jason Roy might have been hoping that The Hundred would help him rediscover his form after a difficult summer so far.
He found runs hard to come by in England's recent white-ball series against India and South Africa, especially in the Twenty20s, and his struggles continued with a first-ball duck against London Spirit on Thursday.
Not quite the start he was after in The Hundred this year after leading the way for the Invincibles in 2021 with 186 runs and two fifties.
With the T20 World Cup fast approaching, it won't just be Invincibles fans hoping that the England opener gets back to his best before long.
And we'll see him soon...
The teams
Welsh Fire: Joe Clarke, Tom Banton, Ollie Pope, Ben Duckett, David Miller, Josh Cobb, Ryan Higgins, Adam Zampa, Jake Ball, David Payne, George Scrimshaw.
Oval Invincibles: Jason Roy, Will Jacks, Rilee Rossouw, Sam Billings, Sam Curran, Jordan Cox, Tom Curran, Matt Milnes, Sunil Narine, Danny Briggs, Mohammad Hasnain.
Post update
Oval Invincibles captain Sam Billings: "We would have bowled first but actually, in a day game, batting first isn't the worst thing to do. It's a bit of a dry pitch as well so who knows? It might slow up a bit towards the end, hopefully.
"It's such a short tournament that every game has extra importance. We'll be looking to put in a strong performance, it's all good sides in the tournament so it won't be easy.
"But what a day, look at the weather, a glorious day in Cardiff to go out and put on a performance."
Post update
Welsh Fire captain Josh Cobb: "Fresh wicket so we're going to use that first up and we'll know what we've got second half.
"There was a lot of individual learning from the first game but one that you want to put behind you and move on. We've back home now in front of a home crowd so looking forward to that.
"Jonny [Bairstow] is a big miss but we've got plenty of batting options, guys who have been playing well, and David Miller is able to come in for us today."
Fire win the toss and bowl
And the news from the middle just earlier was that the Fire will bowl first after winning the toss - and Invincibles' skipper Sam Billings said he'd have gone the same way.
Welcome!
Both of today's sides will be itching put the defeats they suffered in their opening matches firmly behind them.
There's some real talent knocking around these two squads, isn't there? The hosts have Ollie Pope, Tom Banton and David Miller in their ranks while the Invincibles boast Rilee Rossouw, Sam Billings and the Curran brothers in an impressive roster.
But they both came out on the losing end first up, so let's see how they respond in Cardiff today.
Getty ImagesCopyright: Getty Images
Tom Curran and Tom BantonImage caption: Tom Curran and Tom Banton
Live Reporting
Callum Matthews, Sam Drury and Tim Oscroft
All times stated are UK
Invincibles 12-0
Jake Ball, an England international of yore, takes the next five, and is also pretty much on the money.
Roy has a slight alarm as inside edge squirts past leg stump, but he still gets two from it.
Invincibles 5-0
Will Jacks takes two to one of the longer boundaries in Cardiff and then gets into a tangle, almost deflecting the ball down onto the stumps.
Very short straight at this ground, but Payne has not allowed the batters to take a swing yet.
Invincibles 1-0
And it's a wide first up, and off the first legitimate ball Roy pushes to leg for a single.
Post update
Welsh Fire are taking their positions while Jason Roy and Will Jacks emerge through the fire and smoke to stride to the middle.
It's a lovely day in Cardiff too, in fact it's a scorcher!
David Payne is all set to get it going to Jason Roy, here we go.
Get Involved
#bbccricket or text to 81111 (UK only)
We want to hear from you, so don't hesitate to get in touch via #bbccricket or text to 81111 - and don't forget to include your name if texting.
Today's key match-up
Two versatile young stars could be a fascinating match-up today.
Sam Curran is a real threat with the bat, but he could test Tom Banton with ball in hand as the talented batter could be one of Welsh Fire's key players with Jonny Bairstow having left the squad.
Can Roy return to form?
Jason Roy might have been hoping that The Hundred would help him rediscover his form after a difficult summer so far.
He found runs hard to come by in England's recent white-ball series against India and South Africa, especially in the Twenty20s, and his struggles continued with a first-ball duck against London Spirit on Thursday.
Not quite the start he was after in The Hundred this year after leading the way for the Invincibles in 2021 with 186 runs and two fifties.
With the T20 World Cup fast approaching, it won't just be Invincibles fans hoping that the England opener gets back to his best before long.
And we'll see him soon...
The teams
Welsh Fire: Joe Clarke, Tom Banton, Ollie Pope, Ben Duckett, David Miller, Josh Cobb, Ryan Higgins, Adam Zampa, Jake Ball, David Payne, George Scrimshaw.
Oval Invincibles: Jason Roy, Will Jacks, Rilee Rossouw, Sam Billings, Sam Curran, Jordan Cox, Tom Curran, Matt Milnes, Sunil Narine, Danny Briggs, Mohammad Hasnain.
Post update
Oval Invincibles captain Sam Billings: "We would have bowled first but actually, in a day game, batting first isn't the worst thing to do. It's a bit of a dry pitch as well so who knows? It might slow up a bit towards the end, hopefully.
"It's such a short tournament that every game has extra importance. We'll be looking to put in a strong performance, it's all good sides in the tournament so it won't be easy.
"But what a day, look at the weather, a glorious day in Cardiff to go out and put on a performance."
Post update
Welsh Fire captain Josh Cobb: "Fresh wicket so we're going to use that first up and we'll know what we've got second half.
"There was a lot of individual learning from the first game but one that you want to put behind you and move on. We've back home now in front of a home crowd so looking forward to that.
"Jonny [Bairstow] is a big miss but we've got plenty of batting options, guys who have been playing well, and David Miller is able to come in for us today."
Fire win the toss and bowl
And the news from the middle just earlier was that the Fire will bowl first after winning the toss - and Invincibles' skipper Sam Billings said he'd have gone the same way.
Welcome!
Both of today's sides will be itching put the defeats they suffered in their opening matches firmly behind them.
There's some real talent knocking around these two squads, isn't there? The hosts have Ollie Pope, Tom Banton and David Miller in their ranks while the Invincibles boast Rilee Rossouw, Sam Billings and the Curran brothers in an impressive roster.
But they both came out on the losing end first up, so let's see how they respond in Cardiff today.