London - New Zealand captain Brendon McCullum insisted he still had faith in his batsmen after an "hour of madness" cost the team dear in a thumping first Test defeat at Lord's.
England went 1-0 up in the two-match series, with more than a day to spare, after dismissing New Zealand for just 68 to secure victory by the huge margin of 170 runs.
Stuart Broad, who took a Test-best seven for 44, did the bulk of the damage Sunday as New Zealand's pursuit of a victory target of 239 ended inside 23 overs.
An otherwise even contest changed in the hour before lunch on Sunday as New Zealand slumped to 29 for six.
It was the third time in 2013 that New Zealand been six down for fewer than 40 runs.
In the first Test against South Africa at Cape Town in January they were six down for 28 before being dismissed for 45. In the next Test, in Port Elizabeth, they were 39 for six before being bowled out for 121
"For so long in this game we were up with the play and at times we were dictating terms," McCullum, himself lbw to Broad for eight, said Sunday. "Within an hour the game turned on its head.
"Our confidence started to subside and the difference between the two teams came down to that one hour of madness."
He added: "We've had many of these experiences before and I think we've put distance between the last time we felt this sort of pain.
"We've taken some significant steps forward in the last little while but today was undoubtedly a step backwards.
"You've got to give credit where credit's due and Stuart Broad's spell of bowling was high class. He swung the ball beautifully, he was able to get the odd ball to hold its line up the slope and his lengths were impeccable."
To make matters worse for New Zealand both wicket-keeper BJ Watling (knee) and spinner Bruce Martin suffered injuries that made the duo doubtful for the second Test at Headingley starting on Friday.
McCullum took over the gloves at Lord's, having given up keeping in Tests because of back and knee problems.
Should McCullum, rather than reserve gloveman Tom Latham keep at Leeds, New Zealand could field Martin Guptill as an extra batsman.
Meanwhile experienced spinner and fit again former captain Daniel Vettori is due in England this week as a member of the Black Caps' one-day squad.
"There's plenty of different options we have to look at," McCullum said.
"It's important to note that batters have done a very good job for us in the most recent Test matches.
"I totally believe in this group of players and just because of one poor batting performance it's not panic stations," added McCullum, whose side held England to a 0-0 draw in a three-Test series in New Zealand concluded in March.
Sunday's collapse was particularly hard on Tim Southee, whose match haul of 10 for 108 saw him become only the second New Zealander, after fellow seamer Dion Nash in 1994, to take 10 wickets in a Lord's Test.
Southee insisted he did not feel let down by his team-mates.
"No one goes out there to do that deliberately," he said.
"I'm sure we'll learn from that and the beauty of the game is in a few days time we've got a chance to do it all again against the same team."