Sahih Muslim 1280 b

Kuraib, the freed slave of Ibn Abbas, narrated from Usama b. Zaid (Allah be pleased with him) that he had heard him saying: Allah's Messenger (ﷺ) proceeded from 'Arafa, and as he approached the creek of a hill, he got down (from his camel) and urinated, and then performed a light ablution. I said to him: Prayer, whereupon he said: The prayer awaits you (at Muzdalifa). So he rode again, and as he came to Muzdalifa, he got down and performed ablution well. Then Iqima was pronounced for prayer, and he 'observed the sunset prayer. Then every person made his camel kneel down there, and then Iqama was pronounced for 'Isha' prayer and he observed it, and he (the Prophet) did not observe any prayer (either Sunan or Nawifil) in between them (He observed the Fard of sunset and 'Isha' prayers successively.)