Pietersen lifts England

Pietersen forged an impressive sixth-wicket alliance of 161 with Tim Ambrose at his former county headquarters, which helped England close on 273 for seven.

Earlier they had been 86 for five shortly after lunch as New Zealand pushed to level the npower series.

Both Alastair Cook and Michael Vaughan fell before lunch to the swinging ball, which pierced their defences and shattered their stumps, exposing the out-of-sorts middle order.

New Zealand claimed three wickets in 13 balls for just two runs shortly after lunch, leaving England reeling and the future selection of both Ian Bell and Paul Collingwood firmly in doubt.

Andrew Strauss began the mini-collapse by chasing a wide delivery from seamer Kyle Mills and edging to slip just six balls after the interval having previously shown good judgement during a testing morning session.

Just six balls later and Warwickshire batsman Bell, who has failed to convince in recent innings despite helping England home at Old Trafford last week alongside Collingwood, suffered a third-ball duck.

Stepping across his stumps in an attempt to whip a full-length delivery from seamer Iain O'Brien through mid-wicket, Bell missed a straight delivery and provided umpire Steve Bucknor with one of his easiest decisions of the day.

Collingwood, without a Test century in his previous 22 innings, fared no better and having survived a strong appeal for lbw earlier in the over, pushed at a seaming delivery from Mills and edged to slip for another duck.

Gradually Pietersen and Ambrose grew in confidence as the conditions tilted in their favour with Pietersen claiming his first ever Test half-century at Trent Bridge with a clip through mid-wicket off New Zealand captain Daniel Vettori.