The Messenger of Allah ﷺ said, "Whoever enters ihram for both Hajj and Amra, a single tawaf and a single saee suffice for both of them until he exits ihram from both together."
قال رسول الله ﷺ: من أحرم بالحج والعمرة أجزاه طواف واحد وسعي واحد عنهما حتى يحل منهما جميعا.
Tirmidhi (948) and Ibn Majah (2975) both narrated it, from the hadith of Abdul-Aziz bin Muhammad (who is Darawardi), from Ubaydullah, from Nafi, from Ibn Umar, and he related it. Imam Ahmad (5350) also narrated it through this route, and Ibn Khuzayma (2745) and Ibn Hibban (3915) graded it sahih.Tirmidhi said, "This is a hasan sahih hadith, unique in its transmission. More than one narrator has related it from Ubaydullah bin Umar without raising it to the Prophet, and that is more sahih."I say, Tahawi (3830) likewise found fault with it, saying, "This hadith is an error. Darawardi erred in it by raising it to the Prophet ﷺ, whereas its origin is from Ibn Umar speaking about himself. This is how the reliable memorizers narrated it." Nasai also spoke about it, saying, "There is no harm in him, but his hadith from Ubaydullah bin Umar is rejected."I say, Darawardi is trustworthy, and the two Shaykhs and others narrated from him, so it is possible that he related it by meaning, just as Abdul-Razzaq narrated from Ubaydullah, from Nafi, from Ibn Umar, that he combined Hajj and Umrah and performed one saee for both, saying, "This is what the Messenger of Allah ﷺ did." Sufyan also narrated it, from Ubaydullah, from Nafi, from Ibn Umar, "that the Prophet ﷺ performed one tawaf for his combined ihram, and that did not release him from it." Daraqutni (2594, 2595) narrated all of this.For Ibn Umar's statement, "thus did the Messenger of Allah ﷺ do," carries the same meaning as, "whoever enters ihram for both Hajj and Umrah together, one tawaf and one saee suffices him for both." This is because Darawardi narrated the hadith through two routes, once briefly without the story, as mentioned above, and once with the story, as Daraqutni (2591) narrated from him, from Musa bin Uqba, from Nafi, from Ibn Umar, that he entered ihram for Umrah, and when he reached Dhul-Hulayfa he said, "Their matter is but one. I call you to witness that I have merged Hajj into Umrah." So he performed one tawaf for both and one saee for both, and said, "This is what the Messenger of Allah ﷺ did."If this is sahih, then Darawardi did not contradict what others narrated from Ubaydullah bin Umar. It is also possible that Nafi narrated it through two routes, as is established from him in the Sahihayn and elsewhere, so Darawardi narrated from one of these routes while others narrated from the other, and even though the others are more numerous, there is no contradiction between him and them in the meaning of the hadith.By this, Tirmidhi's statement "hasan sahih" is confirmed correct, and his statement that those who did not raise it are more sahih, because they are more numerous, is also confirmed correct. Reconciling between these routes is preferable to declaring the trustworthy narrators mistaken, and Allah, the Most High, knows best.