England Jason Roy and Jonny Bairstow explain the secrets of successful World Cup partnership

Their opening partnership is the envy of global cricket - so what makes Jonny Bairstow and Jason Roy such an explosive duo for England?

The pair gave Rob Key an insight into their preparation as well as their time in the middle ahead of the World Cup semi-final clash against Australia.

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Bairstow and Roy currently average 67.70 at the top of the order - the highest average partnership of all the 113 pairs of batsmen that have opened in at least 15 ODIs.

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Together they have scored 2,099 runs and compiled 10 century stands along the way - the most recent the 123-run stand they shared against New Zealand - and Roy puts their success down to their hunger to succeed.

"I don't think we spend a huge amount of time off the field together - but no-one really does," the Surrey opener reflected.

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"But when we cross over the rope we understand each other's games extremely well; we have fun out there but we also understand when to have fun and when to put our serious heads on.

"We are both extremely driven people as individuals - not just to be good but to be the best; I think that's made a massive difference.

"Naturally that's going to go into our partnership and then we become one of the best partnerships there's ever been. As people we want the best for each other and also the best partnership."

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Bairstow added: "I think there's an understanding as well; if I'm in a bit of a rubbish mood or if I'm not quite revved up raring to go, he'll say something to me and vice versa.

"Nowadays it's the case where if you turn off for 20 balls you're thinking 'what's going on here?' But then if you actually put yourself in the grand scheme of things, it's actually completely irrelevant.

"You might be thinking 'I'm scratching around here' or 'I don't necessarily feel right' but externally people are saying 'that was a good ball', or 'he's grafting here' and 'this doesn't look easy'."

Watch England take on Australia in the second World Cup semi-final on Thursday, live on Sky Sports Cricket World Cup from 9.30am.

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