Devon Conway, anatomy of another successful innings

Devon Conway was 71 not out when Joe Root threw the old ball to Mark Wood, 15 minutes before tea. Other than an announcement over the PA system, there was no way to make the short-ball plan more obvious: fielders were stationed on the boundary at fine leg, long leg and square leg, with three more in close at square leg (again), forward short leg and straight midwicket.

Wood banged his first ball in short towards the ribcage and Conway unfurled a pull shot, as if making a point of hitting it rather than using the ball's pace to deflect it round the corner, and his placement was perfect, somehow finding the gap between two of the boundary-riders. Wood grimaced in frustration at a shot which encapsulated how easy Conway has made Test cricket look in his first two appearances at this level.

England thought that they had found a gap in Conway's armour on the first day of the Lord's Test last week when Wood hit him on the shoulder with a bumper, but he has now hit 40 runs off the 31 short balls he has faced in the series and swivel-pulled with rare elegance, at times resembling Brian Lara with a raised right leg. Conway explained at Lord's that he had been taken aback by the lack of bounce, having grown up playing on fast pitches in South Africa, and once he had adapted to Wood's skiddy short stuff, he was away.

The only surprise came when he whipped Stuart Broad off his pads and straight down Zak Crawley's throat shortly after tea, causing him to throw his head back and shut his eyes in disbelief in his only show of emotion to date. No New Zealand player has scored as many runs across their first three Test innings and few of any nationality can have made such an impression.

"It was good just to be out there in the middle and gain more experience at this level, I suppose," he said afterwards, with typical understatement. "It was all about trying to be nice and positive, as I am throughout any sort of innings. It was a little bit disappointing getting out on 80 - when you get to those positions you'd really like to cash in as much as you can but such is life.

"It's a tough challenge facing two guys [Broad and James Anderson] that have been really successful over a number of years but it's not really about facing the bowler, it's about facing the ball that's presented in front of you and sticking within your gameplan."

Things could have been very different. On 22, Conway had edged a low chance to second slip which was scooped up by Crawley, but stood his ground, waiting for a definitive verdict. Richard Kettleborough gave a soft signal of not out as he referred the decision to Michael Gough, the third umpire, who found no hard evidence that a mistake had been made. It was "Schrödinger's catch - out and not out simultaneously," Daniel Norcross suggested on Test Match Special.

Broad was visibly exasperated, and pundits queued up to criticise the soft-signal protocols, which has already been scrapped in the IPL and will soon be up for debate at ICC level. Jason Holder, the former West Indies captain, tweeted, "How much longer will the soft signal cloud the game?" but in the case of marginal slip catches leaving the decision solely to the third umpire is no silver bullet: issues of foreshortening mean that they are destined to be unclear and contentious regardless.

Conway's only obvious deficiency has been a proclivity to play a fraction outside the line of the ball, bringing chop-ons via the inside edge into play. At Lord's, he inside-edged 25 times against seamers - including once onto his stumps in the second innings - compared to only one outside edge, according to CricViz's data, and the figures were six and three respectively today. He has also had limited exposure to top-quality spin bowling, and will be tested by R Ashwin in the World Test Championship final next week.

Conway was supported ably by Will Young, who gritted things out for just over six hours before inside-edging Dan Lawrence's whirly offspin to short leg via his pad immediately before the close. He was dropped on 7, Root shelling a straightforward catch at first slip as Olly Stone induced an outside edge, and had to cling on for dear life during a probing burst from Broad and Anderson after tea, but he appears to be reaping the benefits of an early-season stint with Durham in which he hit two County Championship hundreds.

Young's success presents a selection dilemma ahead of the WTC final, with Kane Williamson due to return after resting his sore left elbow and New Zealand certain to go in with five bowling options, including an allrounder at No. 7. One batter will be squeezed out and while Ross Taylor has been in a tough run of form over the last 18 months, he survived a characteristically anxious start and reached the close unbeaten on 46 to further his case for retention. Assuming a clean bill of health, that leaves Young as the favourite to miss out despite his 82 - providing further illustration of New Zealand's new-found strength in depth.