England's Andrew Flintoff decided to opt out of bowling practice at England's first preparation session ahead of the fourth Ashes Test raising fears about his on going fitness.

The all-rounder had a bat in the middle, but did not bowl as a precautionary measure.

The 31-year-old has been nursing an injured knee for most of the series which England lead 1-0.

He has so far defied the pain to turn in a man-of-the-match display with the ball at Lord's while returning to form with the bat scoring 74 in England's only innings at Edgbaston.

Fast bowler Graham Onions said: "Everyone knows that Andrew Flintoff is a legend who is a great person to have in our team.

"I think we are a stronger team with him but that is only if he is 100% fit.

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