Cricket World Cup: Jos Buttler admits England were 'completely outplayed' in tournament opener

The 2019 champions were well beaten across all three facets by the Black Caps in Ahmedabad, with a mammoth stand of 273 between unbeaten centurions Devon Conway and Rachin Ravindra putting them away emphatically.

The pair's poise and power put England's 282 for nine firmly in the shade and there will be questions over soft top-order dismissals, patchy bowling and inconsistent fielding.

For a team who have repeatedly set the standard in white-ball cricket over the last eight years and hold both limited-overs titles, it was a chastening start to a long trek around India.

And Buttler made no attempt to sugarcoat the manner of the defeat.

"I'm disappointed. We were completely outplayed," he said.

"I thought we were a long way short of our best with the bat, we were probably looking at 320, 330. We had a lot of starts but I thought we were just a bit off in our execution.

"We weren't quite clinical enough with our shot making and gifted New Zealand a few wickets.

"But we're not robots. Sometimes you don’t play as well as you would like. Everyone's working hard, everyone's prepared well and we were just a bit off it.

"In international cricket when you're a little bit short and the opposition play very well, you’re going to lose the game of cricket."

England are jetting straight off to the Himalayan mountain region of Dharamsala on Friday for their next group game against Bangladesh and, while they are sure to have plenty of doubts and misgivings to mull over on the journey, Joe Root urged them not to second guess themselves too much.

Root, who ended a run of indifferent ODI form with a measured knock of 77, insisted the result was not a dramatic setback to the wider ambitions.

England lost key games on their way to winning the trophy in 2019 and also backed themselves into an early corner before lifting the T20 crown last year.

"It's important that we stay calm. I don't think there's ever been a World Cup-winning side that hasn't had a bump in the road or a stumble along the way," he told BBC's Test Match Special.

"Look at us in 2019, we had hiccups throughout that. We've just got to stay level and authentic to what we are as a team.

"When we do hit a bump in the road, we are a team that comes back strong and we double down on our identity as a team. So you can expect that when we get to Dharamsala.

"We've got to be able to withstand a bit of pressure, soak it up. We are aware of that, we know that is part and parcel of any World Cup journey.

"We've got evidence that our method works, because it has done over a long period of time so we’ve got to stay true to that."

Root also channelled the 'Bazball' philosophy which has carried England's Test team forward over the past 18 months, suggesting that the batting unit could respond to defeat by upping the ante and going even harder next time around.

"We won't be seeing guys chipping it to mid-wicket or mid-off next game, they'll be hitting it 20 rows back," he said.

"That's one example in a number of different areas where we can remind ourselves of how good we are and how intimidating we can be as a batting group.

"We want to double down on that, put sides under pressure and get those massive scores that blow teams away."

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