Marwan had made Abu Huraira as his deputy. and in the hadith transmitted on the authority of Ibn Muthanna (the words are). Abu Huraira was the Governor of Medina.
عَنْ شُعْبَةَ بِهَذَا الإِسْنَادِ وَفِي حَدِيثِ ابْنِ جَعْفَرٍ كَانَ مَرْوَانُ يَسْتَخْلِفُ أَبَا هُرَيْرَةَ وَفِي حَدِيثِ ابْنِ الْمُثَنَّى كَانَ أَبُو هُرَيْرَةَ يُسْتَخْلَفُ عَلَى الْمَدِينَةِ