Buffon has declined the captaincy since he came back. Chiellini offered to him and he said no, humbled himself and said it's not right, probably combination that he just came back and is only backup player now.
It seems it gotten to the degree he doesnt want to be in the way of the rest as in hierarchy of vice captains, so the players were confused who to give it and found Matuidi for most played season seniority for players on the field not named Gigi.