Stunned by Kevin O'Brien's "brutal" hundred, England captain Andrew Strauss was "at a loss" to explain the poor fielding by his team that helped minnows Ireland script an upset win in their World Cup group match in Bangalore.
England dropped four catches, including that of O'Brien (113), in the three-wicket loss on Wednesday which is the biggest upset of this World Cup so far.
"I'm still at a loss to explain that," Strauss said. "We've done the same practice drills. I still think we're an excellent fielding side, but we've put down another three or four catches today and in the end that cost us the game.
"You cannot afford to give away so many chances. If you drop a batsman before, it is hard to get his wicket. It is asking for trouble," he added.
Having posted 327 on the board, England were cruising to a comfortable victory before O'Brien turned the match on its head with the fastest World Cup hundred that came off just 50 balls.
"Obviously we thought we'd done a reasonable job with the bat and we got Ireland at five down and things were looking pretty comfortable," Strauss said.
"But we weren't reckoning on an outstanding innings from Kevin O'Brien. It was pretty brutal and set us back pretty quickly," he added.
England take on title contenders South Africa in the next match and Strauss said he was confident that his team would be back with a bang.
"Generally we bounce back and in the past too. We have done that in Test and one-day cricket. We can be challenging and realise where we could prove. We need to galvanise and we cannot afford any slip up in our remaining matches," Strauss said at the post-match press conference.
Strauss gave full credit to the Ireland team for their victory but said another 10-15 runs more (than 327) would have made the difference.
"It is definitely a disappointing day. Another 10 or 15 runs in the last overs could have helped us. You got to give credit to Kevin (O'Brien) and (Alex) Cusack the way they chased the total down. They got a pretty experienced side. They have done it before in World Cups. They get on to their attitude that they have nothing to lose.
"On the two matches that we have played not one bowler but all bowlers suffered in the wickets. But, you got to get more runs quickly than your opposition teams," said the England captain.
Strauss insisted that England remained a strong World Cup contender despite the shock loss.
"Our World Cup dream's not over by any means," Strauss said.
"We're going to have to bounce back very quickly and learn the lessons from this defeat. We've obviously hemorrhaged runs far too often in all the games we've played."