New Zealand paceman Chris Martin believes Kevin Pietersen is the main threat to the Black Caps' chances of sealing a series victory over England.
The hosts lead 2-0 after the opening exchanges but England's fightback in Auckland means the five-match contest is now poised at 2-1.
New Zealand need to win just one of the last two games to win the series, but they are still not taking anything for granted.
New Zealand seamer Martin believes that, despite not hitting full stride so far this series, Pietersen could be the main danger in the next game at McLean Park.
"He's a tall guy and tends to hit good length balls at the top of the bounce and that makes you wary about the lengths and lines you need to hit because there's a very small margin for error," said Martin.
"At this stage we're keeping him under wraps a little and he hasn't broken out completely just yet, but we're aware he's a very good player."
Pietersen has made just 76 runs in the first three games this series, and his 41 from 65 balls in the last game was far removed from his normal swashbuckling innings.
Martin believes the key to preventing Pietersen from dominating is to keep him quiet early in his innings.
"If you tie him down for a few balls he does have this knack of putting his partner under pressure when they run a quick single," added Martin.
"Most of the guys in the ring have been aware their running has been pretty bad in this series, so when he gets out there it's important to put pressure on him and make sure he doesn't hit boundaries because he can be the guy who runs other people out as well."
England in fact have had seven run-outs so far against New Zealand and the home side are now well aware that chances could be coming up regularly.
Martin added: "We've got a few genuine athletes who are nimble on their feet and pride themselves on their fielding.
"If you're a renowned guy as a run-out king you can still contribute to the team so guys like Ross Taylor and Jamie How can really make an impact in the field if they've had a bad day with the bat."
England's victory in Auckland was a good psychological blow for the tourists as they prevented New Zealand from clinching the series, and another win will test the hosts' resolve.
"We don't want to go to Christchurch at 2-2 and we didn't want to come here at 2-1," Martin admitted
"Each game is another opportunity for us to wrap the series up. If we went into a deciding game from being 2-0 up, that would not be a good prospect for us."