Jos Buttler has voiced the opinion that Brendon McCullum's departure from his role as England's Test coach could actually improve the team's prospects in the upcoming Cricket World Cup, as the former New Zealand captain can now devote his full attention to the limited‑overs format and the quest for the trophy next winter. McCullum was stripped of his red‑ball responsibilities in July, with former New Zealand great Stephen Fleming eventually taking over the Test job.

However, McCullum retained control of England's white‑ball set‑up, a side that finished the summer on a remarkable record of eleven victories and only two defeats across all limited‑overs matches. Those wins included series triumphs over India and Sri Lanka in One‑Day Internationals, a boost for England after a dip in form that followed their 2019 World Cup triumph. In Buttler's view, the split‑coaching arrangement has freed McCullum from the divided focus that comes with juggling both formats.

"He's only got one focus now and that is the white ball," Buttler explained on his "For the Love of Cricket" podcast. He added that while McCullum could technically handle both Test and limited‑overs duties, the reality is that his time and mental bandwidth are stretched thin when he must consider the long‑term demands of the Test side alongside the fast‑paced requirements of the shorter formats.

"Now he can focus solely on white‑ball cricket – T20, yes, but mainly ODI cricket with that World Cup on the horizon," Buttler said. "It seems like Baz is naturally all in on, 'how do I win this World Cup with this team?'" The former New Zealand skipper appears to have embraced a single‑minded mission: to fine‑tune England's 50‑over game, devise strategies, and build a squad capable of lifting the trophy in South Africa and Zimbabwe next year.

Buttler highlighted that the proximity of the tournament makes the target feel tangible. "I think he can sort of see that World Cup is not that far away. It's a real target, now his remit has changed from four months ago being in charge of everything to, 'right, I can really nail down on this'. He's just got more time and more focus on that," the England captain noted.

The shift from a broad, all‑encompassing coaching brief to a concentrated ODI‑only brief allows McCullum to drill deeper into batting orders, bowling variations, field placements, and the psychological preparation required for a high‑stakes knockout competition. The England ODI side has struggled for consistency over the past few years, failing to replicate the dominance they displayed in the 2019 World Cup.

Buttler believes the recent series wins signal a positive trajectory. "ODI cricket for England has not been consistently great for a couple of years, so there's some nice growth to go on that and this summer's been a really good start," he said.

The wins over India and Sri Lanka not only added valuable points but also provided a confidence boost for a group that has been searching for a clear identity in the 50‑over game. Despite the optimism surrounding the coaching setup, Buttler himself is currently sidelined with a hamstring injury.

The injury has already forced him out of the upcoming tri‑series in Pakistan and casts doubt over his availability for the November tour of Australia. If he misses those fixtures, England could be without its most experienced one‑day player for up to eight ODIs and a significant portion of the preparatory work leading up to the World Cup. When asked about his recovery timeline, Buttler explained, "I've had a scan and I'm waiting to see the specialist.

Then we'll know what the next steps are. The unknown is often the tough part. Any cricketer just wants a physio or a doctor to tell you, 'on this date you'll be back playing cricket'.

Unfortunately, they can't do that just yet." His cautious approach underscores the uncertainty that injuries bring to any team's planning, especially when a key batsman and leader is involved. Overall, Buttler's assessment paints a picture of a coaching structure that could pay dividends: a dedicated white‑ball coach with a clear mandate, a squad gaining momentum through recent series victories, and a realistic appraisal of the challenges ahead, including player fitness. If McCullum can translate his singular focus into concrete improvements on the field, England may well be positioned to mount a serious challenge for the 2027 Cricket World Cup, even as they navigate the inevitable hurdles of injuries and form fluctuations.