Hazard was released at the end of the 2022/23 season before retiring last October.
Ancelotti told the Obi One Podcast: “His problem was injuries, of course, but he also had difficulty competing. You have to train intensely in training when you are not playing. It was difficult for him to compete, fight and play.”
Ancelotti also offered his tip for this year's Ballon d'Or.
He said, “In my opinion, Vinicius should win it. He did very well last season. Dani Carvajal also did very well – he won La Liga, Champions League, scored in the final and won the European Championship.
"But Vinicius is young, talented, and he can improve. He won the league, he won the Champions League by scoring in the final, semi-finals, he scored 2 goals in Munich. Jude also had a fantastic season and was the best player in the league.”