It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that "The Prophet (peace and blessings be upon him) gave judgment on the basis of (the claimant's) oath together with one witness."
This hadith is not narrated from Sayyiduna Abu Sa'id (may Allah be pleased with him) except with this chain, and Ja'far bin Abd al-Wahid (may Allah have mercy on him) is alone in narrating it.
Hadith Referenceالمعجم الأوسط / باب العين / 4782
Hadith Gradingمحدثین:إسناده ضعيف لضعف عبد الرحمن بن زيد بن أسلم
Hadith Takhrij«قال الهيثمي: وفيه عبد الرحمن بن زيد بن أسلم وهو ضعيف «مجمع الزوائد ومنبع الفوائد، ج 4، ص 202»» «أخرجه الطبراني فى «الصغير» برقم: 684»