Curran oversteps with final ball giving Spirit another chance
But he then bowls Wood to secure win by two runs
Rossington hits superb 61 off 32 & Critchley nearly wins it with 32* off 13
Invincibles posted imposing 189-4
Jacks (68 off 42), Klaasen (46* off 24) and Sam Curran (35 off 17) all impress
Invincibles now four points clear at top of table
S Curran c Mitchell b Ellis 35 (Invincibles 187-3)
Slower ball and Sam Curran is caught at deep mid-wicket.
Curran tries to clear the ropes but mistimes it a touch, the ball goes a long way up but Daryl Mitchell is calm as you like when it comes back down to earth.
A first wicket for Nathan Ellis.
Four more! Too short and a short-arm jab from Sam Curran sends the ball hurtling through mid-wicket to the boundary.
Slower ball from Nathan Ellis but wide and Sam Curran really throws the bat at it.
The ball comes off the outside edge but goes over the short third fielder for four.
Four balls left.
Steven Finn
Former England bowler on BBC Test Match Special
The Invincibles have propelled themselves to a really formidable total now.
Full and wide from Chris Wood to finish the set, nicely in Sam Curran's arc and he launches it high over long off for yet another six.
Dropped in the crowd. Disappointing.
Steven Finn
Former England bowler on BBC Test Match Special
Sam Curran just waited for that one, knowing it was slower, and allowing him to thrash it straight down the ground rather than square.
This is a dangerous passage of play for Spirit's bowlers.
It's Sam Curran's turn now!
Short and wide from Chris Wood and Curran flat-bats it, baseball-style back over the bowler's head for a huge six!
Klaasen 45, S Curran 14
Six to start the set and six to end it!
Another full toss from Liam Dawson and this time Heinrich Klaasen gets down on one knee and flicks it away over fine leg.
10 balls to go...
Heinrich Klaasen goes again!
It's a gimme from Liam Dawson - a juicy full toss and Klaasen wallops it for another straight six.
Steven Finn
Former England bowler on BBC Test Match Special
He's just hit that like a golf swing straight off the tee.
Daniel Norcross
BBC Test Match Special
That will certainly help get the innings back on track.
Brutal from Heinrich Klaasen!
After two from the first four balls of Nathan Ellis' set, Klaasen launches the last back over the bowler's head for six! Straight as an arrow and six all the way.
Steven Finn
Former England bowler on BBC Test Match Special
I'm not even going to bother responding to that.
Daniel Norcross
BBC Test Match Special
He's done well in the end, the well-seasoned professional Michael Pepper.
Chris Wood's set ends with Heinrich Klaasen drilling a drive back down the ground.
It goes with real pace and actually clips Sam Curran at the other end!
Prior to that Michael Pepper recovered well to prevent a boundary after initially making a hash of a straightforward stop in the deep.
Daniel Norcross
BBC Test Match Special
You have got to be on your toes if you're in the crowd at the moment.
There's the answer! Sam Curran climbs into a full, wide delivery from Chris Wood and sends the ball flying over extra cover for six.
It went very flat again but it carried comfortably over the rope.
Sam Curran is the new batter. Can he and Heinrich Klaasen keep the runs flowing now Will Jacks has departed?
They'll be giving it their best shot.
Melissa Story
BBC Test Match Special commentator
Zak Crawley had to wait an age for that ball to come down but he kept his cool.
It's a very important time for Spirit to take a wicket because the game was just starting to get away from them.
Jacks c Crawley b Mitchell 69 (Invincibles 126-2)
Gone next ball! Caught at deep mid-wicket.
The previous six took Will Jacks past Jordan Cox to become the leading run-scorer in men's Hundred this year but he falls trying to extend his lead.
It was short again from Daryl Mitchell but this time Jacks tried to clear long on - but couldn't get it over the head of Zak Crawley on the rope.