As Brendon McCullum sat in the team hotel reflecting on a humbling first series defeat as England head coach, the idyllic cricket ground in the distance hosting the Barmy Army versus monks from the local monastery – rather than the fourth day of the fifth Test against India – there came an admission that his side’s approach needed refinement.

Though not top of the list, this included an acceptance that some of their public statements on tour had bitten them on the backside; statements such as Ben Duckett in Rajkot saying “the more, the better” regarding the run chase – England crumbled to 122 all out when set 557 – or that Yashasvi Jaiswal, 712 runs by the end, was somehow inspired by the tourists.

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“We do have belief within our group,” McCullum said, 24 hours after the grizzly three-day denouement in the foothills of the Himalayas. “[But] it has taken a bit of a hit over the last couple of weeks. We have to be smarter with those comments. It is fine to inwardly believe what you can achieve but just be a bit smarter around how we say things.

“But it is people growing up in the environment, right. They are not the finished articles yet and surely they shouldn’t be hung for making a positive comment that might be construed as arrogance. It is not arrogance, just confidence in the group.”

If anything, McCullum said, his players should aspire to emulate India, so impressive in securing their 17th successive home series win and not least through an ability to seize the big moments. One example came on day three in Ranchi and the chance to make it 2‑2, only for a lacklustre morning during which England’s overnight first‑innings lead of 134 runs, three wickets required, eroded to just 43 and was followed by a defining collapse.

“They outplayed us at the style of cricket that we want to play and made us start to retreat a little bit,” McCullum said. “India outplayed us, they outskilled us and, in the clutch moments, were just too good for us really. When you are exposed in the way we have been here, you know that you have to get better in some areas.”

McCullum’s diagnosis was that “timidity” set in, even if this may raise some eyebrows given some of the manic batting that unfolded in the final instalment of the 4‑1 defeat. His point here, however, was that their desire to be positive made way for doubt, minds becoming increasingly scrambled by a relentless bowling attack and poor decisions resulting.

Not in the case of one batter, however, with Joe Root’s form heading in the other direction after a low-key start. The personal pivot point for Root was the much criticised reverse-ramp in Rajkot, perhaps a lesson to colleagues about dialling down some of the wilder attempts to spread fields (even if the Yorkshireman has looked to be publicly unrepentant when asked about it).

McCullum said that England’s initial hot streak of 10 wins in 11 under himself and Ben Stokes – a record that now reads 14 from 23 – featured a bit of “luck” that “papered over some cracks”. Tough conversations have been had, he insisted: “On this occasion we’ve got to acknowledge we’ve got a bit of work to do. The next couple of months will be about making sure we are a more refined version of what we are at the minute.”

There is, in fact, a four-month gap before six summer Tests against West Indies and Sri Lanka and while McCullum’s mantra has tended to be about staying present, this gap – with a restart against a lower‑ranked opponent – makes it the halfway point in the project; two years into the head coach’s four-year deal that runs until the end of the 2025‑26 Ashes.

McCullum was cagey about personnel changes but admitted Australia – and the visit of India in the preceding home summer – will start to become a factor in selection. To that end, decisions loom over the long-term wicketkeeper, the first-choice spinner, the middle order and the future of Jimmy Anderson – 700 wickets up – as new seamers are blooded. Gus Atkinson, Josh Tongue and Matt Potts were all name-checked here.

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Both McCullum and Stokes appear in no mood to pension off Anderson, not least given his role as a mentor to those young thrusters. But the 41-year-old remains a tricky one; a seemingly unsated all-time great but one who has taken his wickets at 50 runs apiece this past year. His deployment in India was sympathetic – just 118 overs bowled across the four Tests he played out of a possible 707.5 overs, even as one of four front-liners.

To that end, with Ollie Robinson’s latest comeback another beset by conditioning issues and Mark Wood less threatening in Indian conditions, Potts should probably have joined the squad halfway through after 20 wickets at 17 in three Lions matches against India A. The 25-year-old’s threat was evidenced by a strike-rate of 31, while 104.4 overs across five innings showed his supreme fitness and durability.

McCullum would not be drawn on the expected bottleneck that will follow when Harry Brook returns from the personal reasons that led him to miss this tour, something that affects both Jonny Bairstow and Ben Foakes. The head coach praised both, but said the decision – one that may equally result in an outsider coming in, such as the Durham and Lions keeper Ollie Robinson – will be about “the weaponry to go toe-to-toe with the best teams in the world”.

Regarding the first-choice spinner, there was an admission that heartening maiden Test tours for Tom Hartley and Shoaib Bashir – 39 wickets between them after Jack Leach succumbed to injury – has created another logjam. “Jack will understand that,” said McCullum. “And he will be proud of it, because he is a guy that invests in the team.”

The sense here, given the over‑spin Bashir imparts and that traditionally left‑armers are less effective in Australia, is that the 20‑year‑old may well get the first crack. After a tour of frustration and some humble pie being consumed, it may be that refinement manifests itself in some established positions soon being refreshed.