Close: Eng 116-7, trailing NZ by 16 runs
England lose seven wickets for just 41 runs
Openers Crawley (43) and Lees (25) put on 59 but the rest fall cheaply
Debutant Potts and Anderson claim four wickets each as NZ dismissed for 132
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Potts going off means James Anderson is in the driving seat for a 32nd Test five-fer.
How many injured bowlers would that make it now, nine? Incredible.
That's glorious from Trent Boult though, defiantly smashing the ball through the covers for four.
#bbccricket
Simon Mahon: Doubt this morning Ben Stokes expected to be looking round mid-afternoon at his bowling options to see his spinner is at Warwick services.
Michael Vaughan
Former England captain on BBC Test Match Special
Stuart Broad and Joe Root are back out there so it's good to see them both. It's a real concern for Matthew Potts though, for him to just walk off mid-over.
It's like Piccadilly Circus with subs coming on and off the field all over the place.
Ben Stokes completes the over.
Daniel Norcross
BBC Test Match Special commentator
Oh no, no, no. What is going on here?
What a massive disappointment for that young man.
Oh dear. Potts bowled just two deliveries but is now coming off the field - it is not immediately clear what the issue is.
Trent Boult is in T20 mode as he plays an upper cut over point for three. Colin de Grandhomme then punches the final ball of James Anderson's over backward of square in the offside for a boundary.
It means Matthew Potts will have another shot at Trent Boult next over as he seeks a fifth wicket...
Michael Vaughan
Former England captain on BBC Test Match Special
I've enjoyed New Zealand after lunch. The message was quite clear with the way that Kyle Jamieson played - have a swing and get the scoreboard ticking and if we get bowled out it'll be quickly and there will be some moisture in the wicket.
I still think it is a decent Test match wicket. England have bowled nicely but New Zealand just look rusty, they haven't played enough red-ball cricket.
Trent Boult shuffles in front of his stumps before somehow scrambling the ball backward of square for a single.
Ben Stokes has a smile on his face. Think he is enjoying captaincy so far.
Ha, Trent Boult will not go quietly, showing all three stumps before smashing Potts back over his head for three.
Colin de Grandhomme pushes the final ball of the over into the onside for two, meaning Boult will be on strike for the next over.
There's a standing ovation for Potts as he returns to his fielding position on the boundary.
More oohhs as Trent Boult squirts the ball through to backward point.
Colin de Grandhomme was looking for the quick single but Boult sends him back. All a bit chaotic.
There's a buzz of anticipation around the ground.
Michael Vaughan
Former England captain on BBC Test Match Special
Trent Boult has charged out there. He's ready.
Matthew Potts potentially has five balls to number 11 Trent Boult.
What an opportunity to get on the honours board on debut.
Michael Vaughan
Former England captain on BBC Test Match Special
Scott Boland took, what, 6-7 at the MCG in the winter, Matty Potts has 4-8 now. Can he?
Daniel Norcross
BBC Test Match Special commentator
It was very out - it was hitting middle and leg but four or five inches down the stumps.
Patel lbw Potts 7 (NZ 102-9)
Four reds! Thats out - and Potts has four wickets!
Michael Vaughan
Former England captain on BBC Test Match Special
I think it'll be umpire's call, hitting the top of the stumps.
Daniel Norcross
BBC Test Match Special commentator
I don't think there is an inside edge this time because he took a little while to review.
It might be a bit high.
Potts is bang on the money and traps Ajaz Patel with his first ball back into the attack - but Patel reviews again.
Ben Stokes has yet to bring himself into the attack - Matthew Potts returns instead.