LONDON (Reuters) -- Liverpool defender Martin Kelly has been ruled out for a month with a torn hamstring, the Premier League club said on Tuesday.

The 20-year-old, who has become a regular starter since Kenny Dalglish took over as manager in January, collapsed clutching his leg after a typical surging run in the first half of Sunday's 3-1 defeat to West Ham United.

"Liverpool FC head of sports medicine and sports science Dr Peter Brukner has confirmed the defender is facing four weeks on the sidelines after assessing the injury at Melwood," the club said in a statement on their website (www.liverpoolfc.tv).

The timing of the injury comes as a blow to the Reds who face Manchester United in the Premier League on Sunday before a two-legged Europa League last-16 clash against Braga.

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