Laws of Cricket 1980 Code - Law 14
1. Time of Declaration
The captain of the batting side may declare an innings closed at any time during a match, irrespective of its duration.
2. Forfeiture of Second Innings
A captain may forfeit his second innings, provided his decision to do so is notified to the opposing captain and umpires in sufficient time to allow seven minutes rolling of the pitch. See Law 10 (Rolling, Sweeping, Mowing, Watering the Pitch and Re-Marking of Creases). The normal ten-minute interval between innings shall be applied.
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