Ollie Robinson’s international future has once again become the subject of internal debate among the England hierarchy following a subpar comeback during the team’s series-sealing five-wicket defeat by India in Ranchi.

Speaking in the aftermath of his side going 3-1 down to India with one to play, Brendon McCullum said he would look to support Robinson but, in something of a rarity during his two years as Test head coach, the ultra-positive New Zealander also publicly acknowledged a poor performance from one of his players.

“Everything he did leading into the Test match suggested we’d see not just the Ollie Robinson we’d seen previously but a better version of it,” said McCullum at the team hotel on Tuesday. “For one reason or another it didn’t quite work out for him. Obviously he’s not just as disappointed as everyone else, he’s the most disappointed out of everyone.”

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Ranchi was Robinson’s first appearance in any cricket since walking off the field during the Ashes Test at Headingley last summer with back spasms – itself, not a first – and after 58 runs with the bat, his speeds with the ball hovered in the mid-70s mph. He also struggled with no balls and dropped a pivotal catch during India’s turnaround.

Ben Stokes ignored him completely during India’s run chase and though the captain played a straight bat about this during the post-match press conference, insisting it was solely tactical, England’s frustration behind the scenes has been palpable.

McCullum said: “He actually twinged his back while batting, which is why in those initial couple of spells he was down on pace. It’s a tough game for him, no doubt, and he’s hurting a lot. We’ve just got to make sure we find a way to get the best out of him.”

Injury can strike any player but conditioning – hardiness for the rigours of international cricket – has been a longstanding issue with Robinson. This in turn falls back on the management, however. Despite opting against warm-ups, a 30-year-old with a poor fitness record could have been sent to play for the Lions at the start of the tour, for example.

The upside to Robinson – 76 Test wickets at 23 runs apiece, and lavish skills with the ball from a high release point – is obvious. But whether this fits into a regime that looks to relax players and trust individual drive in preparation is another matter. It was telling last October when England handed a host of young seamers two-year deals but Robinson just one.

Though a side issue, Robinson’s podcast with social media influencer Mia Baker – his girlfriend – has also frustrated a regime battling with public perception. He revealed a visa error by the management at the start of the tour and, in the episode published on Tuesday after the fourth Test, he marvelled at the luxury of the “private jet” the team took from their mid-series break in Abu Dhabi. At England’s request, the episode has subsequently been taken down.

After another break, this time in India but with players splitting between golf in Bengaluru or a resort in Chandigarh, England’s selection in Dharamsala next week may be telling. McCullum spoke of backing Robinson when “the next time arises’’, rather than the fifth Test per se, something he was happier to lock in for Jonny Bairstow.

This will be the Bairstow’s 100th Test cap and one McCullum expects to be a huge motivation after scores of 38 and 30 in Ranchi continued a tour without a statement innings.

“It’ll be really emotional for him,” said McCullum. “Everyone knows Jonny’s story. He is quite an emotional character at times and big milestones like that do mean a lot to him. [In this match] he walked taller, looked stronger, had that presence and that real Jonny Bairstow swagger to him. When he has that you kind of feel he’s never too far away.”

More broadly, McCullum accepted England have been second best at key moments, such as the first innings in Rajkot or day three in Ranchi when Dhruv Jurel’s 90 turned the Test. After the Ashes, 2-2 following a sloppy start and the sense of ‘what if’ after the soggy draw in Manchester, a dynamic style has not been an outright winning one against the best.

“There’s times in games where we haven’t quite screwed down our method just yet,” said McCullum. “We’ve lost here, didn’t win the Ashes, but we’re a better team than 18 months ago and we’ve got an opportunity in the next 18 months to do some special shit. We’ll keep chiselling away at those rough edges. It’s not a bad time to be coach of the England team.”

Amid McCullum’s debrief came praise for Shoaib Bashir and Tom Hartley – 12 wickets between them in Ranchi and 32 overall in the series so far – but a pointed concern about how much cricket they will play domestically given the County Championship is predominantly a spring and autumn pursuit with a heavy leaning towards seam bowling.

At Somerset, the 20-year-old Bashir may find himself vying for one spot with Jack Leach, not least since the spinning tracks witnessed at Taunton in the recent past have been stymied by point deductions. Lancashire, meanwhile, have already signed ­Australia’s Nathan Lyon for the season, potentially blocking out 24-year-old Hartley.

Admitting to “apprehension” when selecting the pair solely for their attributes, given a lack of first-class experience, McCullum said: “We thought they had the skills but would they be good enough at this level? What we’ve seen is they are definitely good enough.

“It will be a slight frustration of ours if they weren’t given opportunities at county level. There’s a very real possibility that might be the case but, without wanting to dictate to counties because they have their own agendas as well, I think you’d be slightly mad if you didn’t give them more opportunities in county cricket.”