It is narrated from Hazrat Aisha (may Allah be pleased with her) that whenever the Prophet (peace and blessings be upon him) sent Hazrat Zaid bin Harithah (may Allah be pleased with him) with any army, he appointed him as the commander of that army: If he had lived after the Prophet (peace and blessings be upon him), the Prophet (peace and blessings be upon him) would have appointed him as his successor.
Hadith Referenceمسند احمد / مسند النساء / 26410
Hadith Gradingحکم دارالسلام:إسناده حسن إن صح سماع البهي من عائشة