"I poured water for him from a small vessel and he performed a light Wudu'. I said to him: 'The prayer.' He said: 'The prayer is still ahead of you.' When he came to Al-Muzdalifah he prayed Maghrib, then they untied the saddles of their mounts and then he prayed 'Isha'."
Sunan an-Nasa'i Book 6, Hadith 116