"I came to the Messenger of Allah and said: "I have come to you from the two mountains of Tai and I have exhausted my camel, and exhausted myself; is there Hajj for me?' He said: 'Whoever offeres this morning prayer with us here, and came to Arafat before that, then he has completed the prescribed duties and his Hajj is complete.'"
Sunan an-Nasa'i Book 24, Hadith 426