Batsmen can create doubt in an umpire's mind by taking a big stride down the pitch with their front foot.
By moving further down the pitch, the batsman lengthens the distance between the ball and the stumps.
If he is struck on the pad a long way down the pitch, the umpire has a more difficult job to assess whether the ball would have gone on to hit the stumps.
But if a batsman is struck while on his back foot or back pad, there is a shorter distance to judge between the batsman and the stumps, strengthening the bowler's appeal for an lbw decision.
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