From back-garden cricket to mowing down England with fastest World Cup ton

O’Brien (113) smashed England to every corner, and over most, at the M Chinnaswamy Stadium in a 50-ball century which turned last night’s Group B match on its head.

He hit 10 fours and six sixes on his way to three figures faster than any other batsman in the 36-year history of the tournament as Ireland completed the World Cup’s highest run chase.

Yet asked whether he thought Ireland had any chance when he came in at 106-4 – soon to be 111-5 – he said: “Honestly? No. But we just took a chance. You cannot write yourself off in any one-day cricket.”

O’Brien, who will be 27 tomorrow, made England’s first-choice attack look horribly exposed albeit on a wonderful batting pitch.

Watched by his father Ginger, a former Ireland captain, and mum Camilla – as well as brother Niall, one of the four batsmen out before him – O’Brien reflected with entirely justified pride on his achievement, and Ireland’s three-wicket win.

He has always been a natural big hitter, but did not usually get the same plaudits when he kept losing the ball as a child.

“That’s a long way the best innings I’ve ever played,” he said. “It even eclipses playing in the back garden with Niall, where hitting it out of the garden was out.”

O’Brien’s captain Will Porterfield made a first-ball duck but unsurprisingly, he too was all smiles at the outcome.

After Ireland’s first cricket win over England in any format, he said: “I think it’s the biggest win Irish cricket has ever had.

“Beating England in any sport is a fantastic occasion, and I’m sure a lot of people back home have been given something to smile about.”

England captain Andrew Strauss will have questions to pose and answer before his side take on South Africa in Chennai on Sunday in what has become a must-win match.

But before then, he could not help but pay tribute to O’Brien.

“It was an outstanding innings – the gall he showed to take the game to us in that situation,” said Strauss.

“He rescued them from a pretty perilous position to one where they were up with the rate and just needed to keep their heads in the end.

“It was a bit of a shock to us, and I’m bitterly disappointed because we did a lot of things badly in the field again.”

England dropped five catches in all, including O’Brien when he was on 91.

Strauss admitted: “We could have taken our catches. I dropped one, and we dropped others as well. That cost us the game – there’s no doubt about it.

“Our bowling could have been better. We got taken by surprise there and we can’t afford to give away those kind of chances here.

“They are very flat wickets and we were asking for trouble.”