"The difference was we were too vulnerable at the back and gave Juventus too many opportunities to cause us problems," Ancelotti said.
"In defence our performance was weak and we conceded soft goals. Tonight we defended zonally on set plays, but Amauri should've been marked on the cross.
"Juve made the most of our mistakes and most of their first half chances came from our errors. We played well throughout and our only real problem was giving away cheap scoring opportunities.
Reflecting on the send off former Juventus player Gianluca Zambrotta, Ancelotti said: "He should've waited in that situation and you cannot risk a tackle like that. These were all incidents that made it an uphill struggle for us.
"We got back into it twice, but when we went down to 10 men as well it became impossible. Our only real regret is that we should've been tighter and more attentive on the counter-attacks."