Cricket World Cup: England's Harry Brook admits he is still trying to 'figure out' ODI format

Just six weeks ago Brook was making plans to watch the tournament from home after being left out of the provisional squad, but things have moved fast since then.

He replaced Jason Roy just before the deadline after an eye-catching response to being left out and, when Stokes suffered a hip injury shortly after arriving in India, Brook found himself promoted from reserve batter to first-choice for games against New Zealand and Bangladesh.

Stokes looks set to miss out again on Sunday, when they face Jonathan Trott's Afghanistan in Delhi, but was running more freely in training at the Arun Jaitley Stadium two days out.

That would give Brook another chance to make the most of his unexpected opportunity in a version of the game that has taken a back seat in the Yorkshire batter's formative years.

Already a rising star in the Test arena and a T20 world champion, he has played a grand total of 23 List A fixtures, with eight of those on the international stage.

With the advent of The Hundred relegating the Metro Bank Cup's status, he is representative of a generation of upcoming English talent with limited 50-over experience and finds himself in the unusual position of learning the ropes at the highest possible level.

"I'm very inexperienced in this format. It does make a big difference having not played it, I think," he said.

"Hopefully I can pick it up fairly quickly after the last couple of games and, if I get another go, then try and make a big score.

"You've just got to try to construct an innings better than I have done in the games I've played, just keep on trying to learn and figure out the format."

Brook has made bright starts in both Ahmedabad and Dharamshala only to be dismissed for 25 and 20.

The numbers tell a story – with his 45 runs comprising 34 in boundaries and coming off just 31 balls. In a side famed for its relentless commitment to attack, there is a suspicion that the 24-year-old may have gone too hard, too soon.

"Everybody's just said 'you've got a lot more time than you think'," he said.

"It's almost approaching the start of your innings like a Test match and then, the longer you're in, the easier it gets and the less the ball's moving around.

"I've played so much T20 cricket over the last couple of years, if you see a ball go above your eyeline your eyes light up and you want to smack it. But I'll just give myself a bit more time and make a big one soon."

England are taking Stokes' fitness on a day-by-day basis, but the next game against an in-form South Africa is likely to be a greater priority than Afghanistan. Either way, there is no question that a place awaits as soon as he gets a green light.

"Obviously Stokesy has to come back in. He's one of the best players to ever play for England," was Brook's assessment. "Whether it's me or someone else missing out, he's 100 per cent coming back in the team."

Chris Woakes was absent from Friday's floodlit training session due to sickness, with Gus Atkinson and David Willey standing by.

The pacy Atkinson has an even thinner track record in 50-over cricket than Brook, playing just five times in the format and taking just six wickets, but has impressed England with his direct, attacking style and has the pace to trouble top batters.

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