Kautilya's Arthashastra 8.5.5

8.5.5

pariśrāntaparikṣīṇayoḥ pariśrāntaṃ snānabhojanasvapnalabdhaviśrāmaṃ yudhyeta, na parikṣīṇam anyatrāhave kṣīṇayugyapuruṣam //

Of tired and reduced armies, the army that is tired may be taken to fight after it has refreshed itself from bathing, eating, and sleeping, but not the reduced army, i.e., the army, the leaders of which have been killed.