If New Zealand really wanted to take it down to the wire and keep us all on our toes they need 1.6 an over!
NZ 124-2
Target 172
Mitchell is not here to hang about, a simply massive six off Theekshana!
It was picked early and Mitchell wasted no time in dispatching that over the rope at long-off. The total continues to climb for New Zealand.
NZ 118-2
Target 172
Not the start there that Mathews would have wanted, with 10 runs coming from the other.
Just over 50 more to go for the Black Caps, whose victory is almost an inevitability now rather than a possibility.
Post update
Daniel Norcross
BBC Test Match Special commentator
Williamson plays the most sumptuous backwards drive.
NZ 116-2
Target 172
Angelo Mathews has given away runs off every ball in his first over so far, but it takes all of four balls for Williamson to find the boundary.
A back foot punch through the covers goes a way towards knocking this target down.
Post update
Daryl Mitchell has not been in for long, but he's played a couple of brilliant reverse sweeps already.
NZ 108-2
Target 172
Not that New Zealand will be looking, but if they were not in a rush from here, they require less than two an over to win, with 34 overs still to go.
Mitchell already sits on 18 off 11. Meanwhile, Williamson has scored a much more conservative three runs off nine balls.
Post update
Rachin Ravindra will be disappointed not to still be batting. Here is how he departed on 42.
NZ 108-2
Target 172
Four more from Mitchell and the number of runs required is very quickly tumbling for the Black Caps.
Theekshana this time is the victim, with Mitchell again reverse sweeping to beat deep point and find four.
Post update
Daniel Norcross
BBC Test Match Special commentator
New Zealand can smell the semi-finals!
Post update
Henry Moeran
BBC Test Match Special commentator
A lovely flurry of the bat, It's been exactly the day that New Zealand wanted.
NZ 103-2
Target 172
That proved to be an expensive over, with 11 runs coming from it in total.
A mid-wicket drive from Mitchell off the final ball takes New Zealand into three figures, with less than 70 needed to win from here.
Post update
Henry Moeran
BBC Test Match Special commentator
Lovely, lofted drive. Away it goes. Daryl Mitchell has done a number of shots like that!
NZ 99-2
Target 172
No chance! Mitchell goes big!
It's an aerial drive that flies over the rope at mid-off.
This could be a very entertaining watch.
NZ 93-2
Target 172
Sri Lanka look semi-interested as Chameera's delivery whistles past Mitchell's bat. They debate a review, but opt not to, the right call.
Surely, New Zealand can't collapse from here?
NZ 92-2
Target 172
Nothing more to come from the other, but two wickets does halt the momentum slightly and give Sri Lanka a bit of belief.
Kane Williamson and Daryl Mitchell, however, do not want Sri Lanka's resurgence to last long.
Post update
Henry Moeran
BBC Test Match Special commentator
Mitchell with the reverse shot. Beautiful!
NZ 92-2
Target 172
One ball, four runs. Daryl Mitchell is not hanging about here.
Having claimed the wicket of Ravindra in the previous ball, new batter Mitchell instantly puts the pressure back on the bowler, reverse sweeping that for four.
As starts go, that is pretty impressive.
Post update
Henry Moeran
BBC Test Match Special commentator
Ravinda has lost his shape entirely!
That might just hold things up for New Zealand.
WICKET
Ravindra c De Silva b Theekshana 42 (NZ 88-2) Target 172
This wasn't in the script!
Wickets in back-to-back overs for Sri Lanka and again, Ravindra, who was in good touch, goes just short of another half-century.
Ravindra, again taking the attacking approach, looked to take that delivery on but picks out De Silva at mid-on and is heading back into the sheds.
His departure does bring out Daryl Mitchell, who will certainly look to go quickly.
Live Reporting
Jonty Colman and Ffion Wynne
All times stated are UK
Post update
Alex Hartley
Former England bowler on BBC Test Match Special
If New Zealand really wanted to take it down to the wire and keep us all on our toes they need 1.6 an over!
NZ 124-2
Target 172
Mitchell is not here to hang about, a simply massive six off Theekshana!
It was picked early and Mitchell wasted no time in dispatching that over the rope at long-off. The total continues to climb for New Zealand.
NZ 118-2
Target 172
Not the start there that Mathews would have wanted, with 10 runs coming from the other.
Just over 50 more to go for the Black Caps, whose victory is almost an inevitability now rather than a possibility.
Post update
Daniel Norcross
BBC Test Match Special commentator
Williamson plays the most sumptuous backwards drive.
NZ 116-2
Target 172
Angelo Mathews has given away runs off every ball in his first over so far, but it takes all of four balls for Williamson to find the boundary.
A back foot punch through the covers goes a way towards knocking this target down.
Post update
Daryl Mitchell has not been in for long, but he's played a couple of brilliant reverse sweeps already.
NZ 108-2
Target 172
Not that New Zealand will be looking, but if they were not in a rush from here, they require less than two an over to win, with 34 overs still to go.
Mitchell already sits on 18 off 11. Meanwhile, Williamson has scored a much more conservative three runs off nine balls.
Post update
Rachin Ravindra will be disappointed not to still be batting. Here is how he departed on 42.
NZ 108-2
Target 172
Four more from Mitchell and the number of runs required is very quickly tumbling for the Black Caps.
Theekshana this time is the victim, with Mitchell again reverse sweeping to beat deep point and find four.
Post update
Daniel Norcross
BBC Test Match Special commentator
New Zealand can smell the semi-finals!
Post update
Henry Moeran
BBC Test Match Special commentator
A lovely flurry of the bat, It's been exactly the day that New Zealand wanted.
NZ 103-2
Target 172
That proved to be an expensive over, with 11 runs coming from it in total.
A mid-wicket drive from Mitchell off the final ball takes New Zealand into three figures, with less than 70 needed to win from here.
Post update
Henry Moeran
BBC Test Match Special commentator
Lovely, lofted drive. Away it goes. Daryl Mitchell has done a number of shots like that!
NZ 99-2
Target 172
No chance! Mitchell goes big!
It's an aerial drive that flies over the rope at mid-off.
This could be a very entertaining watch.
NZ 93-2
Target 172
Sri Lanka look semi-interested as Chameera's delivery whistles past Mitchell's bat. They debate a review, but opt not to, the right call.
Surely, New Zealand can't collapse from here?
NZ 92-2
Target 172
Nothing more to come from the other, but two wickets does halt the momentum slightly and give Sri Lanka a bit of belief.
Kane Williamson and Daryl Mitchell, however, do not want Sri Lanka's resurgence to last long.
Post update
Henry Moeran
BBC Test Match Special commentator
Mitchell with the reverse shot. Beautiful!
NZ 92-2
Target 172
One ball, four runs. Daryl Mitchell is not hanging about here.
Having claimed the wicket of Ravindra in the previous ball, new batter Mitchell instantly puts the pressure back on the bowler, reverse sweeping that for four.
As starts go, that is pretty impressive.
Post update
Henry Moeran
BBC Test Match Special commentator
Ravinda has lost his shape entirely!
That might just hold things up for New Zealand.
WICKET
Ravindra c De Silva b Theekshana 42 (NZ 88-2) Target 172
This wasn't in the script!
Wickets in back-to-back overs for Sri Lanka and again, Ravindra, who was in good touch, goes just short of another half-century.
Ravindra, again taking the attacking approach, looked to take that delivery on but picks out De Silva at mid-on and is heading back into the sheds.
His departure does bring out Daryl Mitchell, who will certainly look to go quickly.