Tom Curran says that he is learning to vary his deliveries as he tries to improve and win a place in England's 2019 World Cup squad.
Curran is part of the England squad currently playing in New Zealand and which could seal the ODI series if they win in Dunedin on Wednesday to take a 3-1 lead.
It's about me putting my hand up and performing when I do get given a chance.Tom Curran
The 22-year-old who plays for Surrey, says he is a "work in progress" as he seeks to perfect the specialist skill of death bowling in the last overs of an innings.
He has played in all three matches of the current series so far, taking just the one wicket and concedes he has much to learn when it comes to bowling when the pressure is on.
He told Sky Sports: "You have time in training to get a feel for all these different slower balls - and if you don't try them, you're not going to learn. It's a gut instinct, and out there I make a decision and commit to it.
"I'm practising all the time, trying these new ones. There's obviously the knuckleball, and there are other slower balls that are coming out.
"In games at the moment, I'm just using the two. But there'll be a couple more interesting ones coming out for the season - a work in progress."
Curran made his ODI debut for England last summer, against the West Indies and has played in six so far, taking eight wickets at an average of 34.25.
He says he is delighted to be in the squad and hopes to stay there for the fast-approaching World Cup next year.
"That's exciting - it's a great place to be in. It's about me putting my hand up and performing when I do get given a chance," he added.
"It's 15 months away, so I'll finish this tour, go back, do my thing for Surrey and hope to give Morgs a tough selection problem."
England are 4/5 to win the fourth ODI against New Zealand with the Black Caps priced at 1/1.
Curran is 9/2 to be England's top bowler in the match.
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