Tim Southee cited England spearhead James Anderson as the key man New Zealand had to counter after bowling the tourists back into an evenly-poised first Test at Lord's.
The Kiwi paceman took three wickets for four runs in 17 balls late on Saturday to leave England 180 for six in their second innings at stumps on the third day -- a lead of 205.
However, that advantage was almost as much as New Zealand's first innings 207.
Anderson, who on Friday became only the fourth England bowler to take 300 Test wickets, finished with an innings return Saturday of five for 47.
Part-time New Zealand bowler Kane Williamson later turned one sharply to dismiss Jonathan Trott for 56, prompting fears about the damage England off-spinner Graeme Swann might do in the rough created by the Kiwi left-arm seam duo of Trent Boult and Neil Wagner.
But Southee reckoned Anderson was still the man to watch.
"The swing of James Anderson is also an issue. He showed his class in the first innings and has a great record here," Southee said.
England were well-placed at 159 for two before Southee removed Joe Root for 71 after the Yorkshireman got an inside edge onto his middle stump.
"It's quite a slow pitch -- you've got to really work hard to start with," said the 22-year-old Root, playing his first Test in England and only fifth in all.
"I was very disappointed not to kick on and, after giving them a sniff tonight, we're quite down about it.
"Hopefully we can have a good morning and build a platform to win the game."
Root's exit was the cue for a dramatic slump that saw Southee dismiss Jonny Bairstow (five) and then capture the prize wicket of England dangerman Matt Prior for nought for the second time in the match.
Southee added that some straight talking by New Zealand captain Brendon McCullum and the normally mild-mannered Williamson had got the side back on track after Trott and Root's third-wicket stand of 123 threatened to take the game away from the tourists.
"The guys ambled through the first half of that session and Brendon pulled the guys in at drinks and Kane gave us a few stern words. It did need something, it was meandering along and England were cruising a little bit," Southee said.
"Everyone just lifted a little bit and we got one wicket and we were lucky enough to pick up a few."
However, Southee warned there was much work left for New Zealand if they were to go 1-0 up in this two-match series ahead of next week's second Test at Headingley.
"We can't get too far ahead of ourselves. We've still got a job to do."
New Zealand saw both wicket-keeper BJ Watling (knee) and left-arm spinner Bruce Martin (calf) go off injured on Saturday, with former Test gloveman McCullum taking over behind the stumps for most of the final session.
Watling and Martin will have their fitness assessed before play resumes Sunday.