Hassan said in a gathering that included Abu Hurairah, "I ask you by Allah, Abu Hurairah, did you hear the Messenger of Allah ﷺ say, 'Answer on my behalf. O Allah, support him with the Holy Spirit'?"Abu Hurairah replied, "By Allah, yes."
حدثنا عبد الرزاق أخبرنا معمر عن الزهري
أن حسان قال في حلقة فيهم أبو هريرة أنشدك الله يا أبا هريرة هل سمعت رسول الله ﷺ يقول أجب عني أيدك الله بروح القدس فقال اللهم نعم
Its isnad is sahih. Muslim related it in 2:259 through the route of Abdul-Razzaq from Mamar, with this same isnad. He also related it both before and after this, through other routes, at length and in brief, from Abu Hurairah. Bukhari related it in 6:221 through the route of Sufyan, who is Ibn Uyayna, from Zuhri, with this same isnad, at length. He also related it in 1:456 and 10:453, with two other isnads, from Zuhri, from Abu Salama bin Abdul-Rahman, from Abu Hurairah. The Hafiz said that this comes from the narration of Saeed bin Musayab, from Abu Hurairah, or from Hassan, and that he did not witness this exchange with Hassan, since the narration of Bukhari and Muslim states that this exchange took place in the time of Umar. Ismaili related it through the narration of Abdul-Jabbar bin Ala, from Sufyan, who said, "I did not memorize this from Zuhri except from Saeed, from Abu Hurairah." According to this, it seems Abu Hurairah told Saeed the story some time after it occurred. This is why Ismaili said, "The wording of Bukhari's version has the appearance of being a disconnected (mursal) narration." And it is as he said. The answer to this has become clear through this narration.