After the semi-final defeat against India in the men’s T20 World Cup last month – a match of tactical missteps that undermined England on the day – Matthew Mott claimed his partnership with Jos Buttler had been “galvanised” by the campaign and, given the chance to continue, the team would come back “bigger, badder and better”.

Four weeks later, however, the Australian’s faith in their relationship as head coach and captain has proved to be unrequited. Rob Key, the men’s team director, held separate talks with both men before announcing on Tuesday that Mott had “stepped down”. With Buttler staying on as captain, and Marcus Trescothick stepping up as interim head coach for Australia’s visit in September, the captain’s consent here is implicit.

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Rewind to late 2022 and they were a winning ticket, England uniting the two white-ball titles by following their 50-over World Cup triumph in 2019 under Eoin Morgan and Trevor Bayliss with victory in its T20 equivalent. Beating Pakistan in the final made for a heady night at the MCG and while there was a nagging suspicion it owed much to the foundation laid by their predecessors – Mott and Buttler had come together six months earlier – a golden time for England in limited-overs cricket appeared set to roll on.

In a cramped schedule, the job became less about bilateral results and more about the global events every year. The first of the two crowns was lost in gruesome fashion in India last winter, a campaign of six defeats in seven “live” group games summed up by the heavy loss against South Africa in Mumbai, when Buttler opted to bowl in 37.5C heat and Heinrich Klaasen’s incendiary 109 left his players seeing pink elephants. “It was probably hotter than we gave it credit for,” Mott said, setting alarm bells ringing as he did so.

Key, who had initially hired Mott to keep a good thing going alongside Morgan, tried to absorb the blame for India and, accepting it owed much to an ageing team and resources going to the Test side, offered the pair a second chance. The T20 World Cup in the Caribbean that followed was not exactly a case of win or bust – the format is too volatile to make it so – but, after three defeats and one win against full member opposition, thrashing the associate sides could not mask the scant progress made.

Players left the tour privately grumbling about the messaging; a supposed freedom to express themselves while at the same time being issued with prescriptive, other-thought instructions. Once Key began canvassing views during the recent Test series against West Indies, the status quo became untenable. Not that the fingers were necessarily being pointed at the head coach in this regard.

The biggest questions are why Buttler has been backed to continue – why he wants to continue, also – and why Mott, a decent man with strong credentials, has been the one to make way. Coaches are seen as easier to remove and replace but, outwardly at least, Buttler has not appeared to enjoy the captaincy of late.

A shout to be England’s greatest white-ball batter, Buttler’s lowly returns in the past two World Cups have not helped the team. The decision-making has also been questionable; that toss in Mumbai, the “gut call” to open the bowling with Will Jacks in the T20 group game against Australia, despite a short boundary and a gale blowing into it, or the semi-final against India when, on a spinning pitch, and with four seamers in the team, he failed to throw the ball to Moeen Ali.

Captaining from behind the stumps – having to sprint to the other end to speak to the bowlers – has probably not helped Buttler, even if he has always dismissed this notion. Although dismissiveness has been a theme of his media duties: while only a small part of the job, the best captains, such as Morgan, understand they are a chance to share their messaging with the public, rather than the person asking the question.

As a sought-after talent in the franchise world, a double World Cup winner, and turning 34 in September, it could be that the captaincy is what is keeping Buttler in the England fold. Although it may just come down to his stubbornness and a lack of ready alternatives. England are overdue a reboot of white-ball personnel, while the cramped schedule essentially rules out those in the Test team from taking over. Harry Brook, for example, cannot play every series and bilateral white-ball tours will be the ones to make way.

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Neither reason is an ideal starting point for Key’s “new direction”, although he clearly believes a fresh head coach can unlock the best of Buttler and that the Champions Trophy next year will show this. Given it is a 50-over tournament, it should really be a proving ground for the World Cup in 2027, by which time Buttler will be 37. That said, who knows what the landscape will look like by then given the march of the franchises.

If interested in the head coach role full-time, Trescothick will be among the favourites given his chance to impress at the end of the summer and a close working relationship with Buttler that goes back to their Somerset days. Other names doing the rounds are Kumar Sangakkara, Buttler’s director of cricket at Rajasthan Royals, Mike Hussey, who was a consultant coach for England’s T20 win in Australia, and Kieron Pollard, who Buttler leaned on for tactical advice in the Caribbean.

Andrew Flintoff was also on that tour but while his return to cricket after the awful car crash in 2022 has been heartening, it would be a problematic appointment given his friendship with Key and that Richard Thompson, chair of the England and Wales Cricket Board, has acted as his agent in the past. Morgan, enjoying commentary and time with his young family in retirement, has already ruled himself out. Andy Flower, who has enjoyed success on the franchise circuit since his England days, is a stronger shout.

Whoever gets the job – and the landscape is not flush with willing candidates due to those less intense and better paid gigs in the T20 world – Key will need them to gel with Buttler or face questions about his own judgment.