Ibn Abi Marhab (may Allah be pleased with him) said: Four men went down into the grave of the Messenger of Allah (peace and blessings be upon him); one of them was Abdul Rahman bin Awf (may Allah be pleased with him). And Sayyiduna al-Mughirah bin Shu'bah (may Allah be pleased with him) used to be called the last of the people to have been in contact with the Messenger of Allah (peace and blessings be upon him). (He used to say:) "So I am the last of the people to have been in contact with him (peace and blessings be upon him)."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17988