Imam Abu Bakr, may Allah have mercy on him, says that in the narration of Sayyiduna Abdullah bin Zubair, may Allah be pleased with them both, when the sun had declined, the Noble Prophet, peace and blessings be upon him, delivered a sermon, then combined and performed the Zuhr and Asr prayers.
Hadith Referenceصحيح ابن خزيمه / جماع أبواب ذكر أفعال اختلف الناس فى إباحته للمحرم، نصت سنة النبى صلى الله عليه وسلم أو دلت على إباحتها / 2807