BBC Sport - London Marathon: Mo Farah: 'Big ask' for four-time Olympic champion to win - Radcliffe

'Big ask' for Farah to win London Marathon - Radcliffe

Marathon world record holder Paula Radcliffe believes it is a big ask for Mo Farah to win this year's London Marathon.

Radcliffe also says the women's world record she set in London in 2003 is also under threat this year.

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