Baby-faced Root shows maturity
There must be something disconcerting about being thwarted by Joe Root. Like being held at gun point by a toddler, there is something incongruous about the baby-faced batsman providing such mature resistance.
Root, the youngest player on either side, has not just produced the highest innings of this match to date but may well have struck the defining blow. His stand of 123 with Jonathan Trott is the single century partnership of the game so far and England's only half-century stand. The lead is still only 205 but, on a pitch that is providing substantial assistance for the offspin of Kane Williamson, England may well hold the trump card with Graeme Swann to bowl in the fourth innings. He will rarely have conditions more in his favour.
The true value of the partnership between Root and Trott was put into context by what preceded and followed it. Just as New Zealand lost their last seven wickets for just 60 runs (including six for 52 in the morning session) so England lost four wickets for 12 runs in 39 balls once Root was dismissed by Tim Southee's well-disguised offcutter. Such evidence would suggest that this slow pitch remains desperately demanding for batsmen. Scoring the highest total of the match in the fourth-innings - which New Zealand may well have to do - will not be easy.
The notable feature of Root's innings was how few of his runs came from drives. All eight of his boundaries came square, or just backward of square, of the wicket and only one run came in the V between mid-on and mid-off. He pulled or hooked the fast bowlers particularly well, cut the spinner nicely and, despite one or two misunderstandings with Trott, maximised their scoring opportunities with some swift running between the wickets.
Perhaps England had some fortune. Root and Trott batted through the only period of sustained sunshine in the game and New Zealand struggled to obtain the swing they had generated in the first innings. On the face of things, the loss of Bruce Martin, the left-arm spinner, to a calf strain in the evening session might have been a body blow to New Zealand as well, though it actually brought Williamson into the attack. Bowling his offspin quicker and a little straighter than Martin, he immediately proved more demanding. Swann will have observed with interest.
Trott's suitability for such situations needs little reiteration. Suffice it to say, his sound defence and determined temperament render him an ideal player to negate a striving attack in match-defining situations and he has now scored a half-century at least in all seven of his Tests at Lord's. But, so impressive was Root that he looked the more assured of the pair for much of their partnership. It was a remarkably calm display from a man not just in his fifth Test but playing his first game at any level at Lord's. Both his younger brother and father have played at this ground before him.
Perhaps he was helped by that family influence. His younger brother, Billy, is in the England dressing room for this game, fulfilling 12th man duties, while his parents and grandfather were among the spectators at the ground. But such aids are peripheral: when it comes down to facing international bowlers such as Neil Wagner - a man who surely looked older than Root even in his prenatal scans - he is all on his own. He coped admirably.
It may prove relevant that Root's best performances to date - this game and his debut match against India in Nagpur - have taken place on unusually slow wickets. Perhaps, when international teams have had a chance to analyse his technique, he will undergo a fallow period and certainly the Australia pace attack will provide a different test. But whatever happens, Root has underlined the impression that he is a young man with a long future at this level.
Such is his apparently unflappable temperament and his ability to adapt his game to the differing demands he has faced - he has also impressed in his ODI opportunities - that few would bet against him finding a way to overcome whatever obstacles life presents. Forget the boyish exterior - really, he might struggle to be served in one of the bars on this ground - where it matters, in his head, he is as cool and calm as anyone.
His success is also testament to the system that helped produce him. Root had not enjoyed an especially outstanding season in 2012 but, such was the good impression he had made while involved in the England Lions set-up, he won selection on the Test tour to India. It has proved an inspired decision and one for which the England selectors and staff - particularly Graham Thorpe, who pinpointed his attributes - deserve much praise. It might also prove a timely reminder of the worth of the Lions system, imperfect and inconvenient to the domestic game though it may sometimes appear.
"We played exceptionally well for the majority of the day and hopefully we can take that confidence into tomorrow and get a good partnership in early," Root said afterwards. "It's very disappointing not to finish as strongly as we would have liked, so the first hour tomorrow will be crucial.
"The rough outside the right-handers' off stump is encouraging and Graeme Swann will look at that and enjoy it. The pitch is quite slow and is obviously deteriorating. The longer we can stay out there the harder it will for them."
Some will suggest that his most recent success again poses a threat to Nick Compton. It is true that Root, coming in at No. 4 due to Ian Bell's incapacitation with "flu-like symptoms", has played as an opener for Yorkshire and that, in time, he may well move up to perform the same role for England. And it is true, too, that Compton, late on a pleasing inswinger from Wagner, has done his case few favours in this game.
But England's success in recent years was not built on cut-throat selection and it is not so long since Compton contributed back-to-back centuries in New Zealand. It is encouraging to have options and the likes of Varun Chopra, James Taylor and Ben Stokes ensure that a healthy competition for places remains.
George Dobell is a senior correspondent at ESPNcricinfo