The server must stand behind the baseline, between the centre mark and the sideline.
A 'foot fault' is called if any of the following happens before the ball is struck:
The feet touch the ground inside the baseline
The feet touch the wrong side of the centre mark OR
The feet touch the wrong side of the imaginary extension of the sideline.
A foot fault is the same as a fault on a serve so the player is given the chance of a second serve.
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