New Zealand v Australia: Black Caps opener Devon Conway in ...

The main event of the summer was always going to occupy the Black Caps’ attention over a whirlwind warm-up act.

But now the lost T20 series against Australia is threatening to impact their bid for a rare test win over the transtasman rivals.

Friday night’s 72-run defeat at Eden Park could have hurt more than New Zealand’s now-futile attempt to win back the Chappell-Hadlee Trophy, with Devon Conway in doubt for the first test at the Basin Reserve.

The opener copped a blow to the left thumb while wicketkeeping during game two, ceding the gloves to Finn Allen and leaving the stadium as the Black Caps’ 10 batters crashed to 102 all out.

An X-ray cleared Conway of an obvious fracture and he returned to Eden Park to watch his understrength side fall to a second straight defeat, rendering Sunday’s third match a dead rubber.

Conway will play no part as he heads home to Wellington and sees a hand specialist, giving coach Gary Stead an anxious wait ahead of the start of the first test on Thursday.

“It’s still a bit unknown,” Stead said. “He had some strange things going on with his thumb, it was clicking a little bit. But at this stage, he has been cleared of a break, which is great.

“There is a little bit of a concern because we’re not 100 per cent sure yet exactly how it’s going to respond over the next few days. We’ve still got a little bit of time, and I think it’ll come down to pain management and what he can do around making sure he feels comfortable at the crease.”

Conway had looked uncomfortable for much of the summer, enduring a slump across all formats. But a return to form seemed close when he struck a scratchy half-century in the final-ball defeat by Australia in game one.

The 32-year-old could have used another couple of innings before walking out alongside Tom Latham at the Basin. Now, Will Young appears a probable replacement, with news more positive for the rest of the batting order.

Kane Williamson will take his place at No 3 after he and wife Sarah celebrated the birth of their third child, timing the arrival between test series as well as he does a cover drive.

Stead is “very confident” about the health of No 4 Rachin Ravindra, whose niggly left knee has him unlikely to play the third T20 after being a late scratch from game two.

And Daryl Mitchell was tracking well to return from a foot injury that saw him sit out the second test against South Africa, when Young batted at No 5 and joined Williamson in a series-clinching stand.

The absentee list will give the Black Caps a makeshift look on Sunday afternoon, though that is partly by design, with Stead making a point of prioritising the tests before naming his T20 squad.

It’s an understandable approach. The short-form games are essentially preparation for the T20 World Cup in June, while the five-day contests carry World Test Championship points.

Every New Zealand cricket fan remembers Hobart 2011 as the occasion of the Black Caps’ last test triumph over Australia — there are only eight, after all — while the T20s will be forgotten by next week.

Given the injuries, Stead is unconcerned by the results, with only a few centimetres keeping the Black Caps from winning the opening T20 in Wellington.

“We have got that first test in mind and making sure the players we want to be fit and available for that are,” he said.

“We’re still realistic around where we’re at. Yes, we didn’t get the results we wanted to, but there’s a number of guys who will come back into our side around the World Cup, which will make a big difference in terms of the experience they bring.”