Cricket World Cup: Kevin Pietersen flying home for op

Pietersen has scored 131 runs in England's first four World Cup games

Kevin Pietersen has been ruled out of the rest of England's World Cup campaign because his hernia problem is more serious than first thought.

The 30-year-old opener will be replaced by Middlesex batsman Eoin Morgan.

England had hoped Pietersen would play through the pain before having hernia surgery after the tournament.

But the decision was taken to fly him home on Monday after he struggled in the field during the six-run win over South Africa on Sunday.

England coach Andy Flower told BBC Sport: "The medical advice was that he could get through the tournament.

"The hernia problem that he had would not get significantly worse and he wasn't going to tear anything so we hoped that he would get through the tournament ok, take pain killers when needed and bite the bullet.

"Unfortunately he says that the pain is too debilitating and he can't go on like that, so it's a pretty simple decision in replacing him."

The hernia problem was initially discovered after an MRI scan following Pietersen's return to England after the post-Ashes one-day series in Australia, which the home side won 6-1.

Before Sunday's game, Pietersen had shown signs of returning to the form that resulted in him equalling the record as the fastest player to score 1000 one-day runs, notching up 129 runs in England's first three World Cup games.

Opening the batting with captain Andrew Strauss he scored 39 against the Netherlands, 31 against India and 59 in the defeat to Ireland, before making only two runs in Sunday's Group B win in Chennai, though he did manage to bowl eight overs.

On his departure from the tournament, Pietersen told his Twitter page: "Absolutely devastated!! Sad to leave India. Love the people & the hospitality!"

BBC cricket correspondent Jonathan Agnew said: "Although he has scored only two fifties in the last 27 games, Pietersen was a potential match-winner and England's dilemma will be deciding who now opens the batting in his place, with Ravi Bopara and Ian Bell the likely candidates."

Pietersen's injury requires around six weeks of recovery and will also rule him out of the Indian Premier League, which he was due to contest with the Deccan Chargers.

Morgan, one of the best finishers in the one-day game, was originally ruled out of the tournament with a broken finger.

But he has made a quicker-than-expected recovery and will join up with the squad this week after receiving clearance from the International Cricket Council's six-man Event Technical Committee.

The Dublin-born left-hander, who played for Ireland in the last World Cup before switching to play for England, has a batting average of 38.08 from 61 one-day internationals, with four hundreds and 10 fifties.

An inventive stroke-maker, he was a key member of the England side that won the ICC World Twenty20 last year.

However, he did not score more than 30 in any of his six innings during the 6-1 defeat by Australia before succumbing to a broken finger.

"His finger has healed nicely and he has full flexibility back into the joint," Flower added. "He hasn't done any training yet, so we'll get him straight into the nets and up to speed as well as we can."

England will be guaranteed a place in the World Cup quarter-finals if they beat co-hosts Bangladesh on Friday.

Flower said he had already decided who would open the batting in Chittagong, but suggested the opening pair could be decided on a game-by-game basis.

"What that can give us is flexibility," he said. "We should remain adaptable depending on what the opposition is and what the pitch conditions are."

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