The hosts appeared to be on their way to the full three points when Thomas Heurtaux gifted them a 2-1 lead in the 71st minute, but Christophe Jallet decided different as he salvaged a draw for the Ligue 1 leaders in the dying minutes of the game.
"Caen played really well and scored from some of their chances. But we showed the character to score in the closing minutes. It's a good day because our gap over Montpellier has increased by a point," Ancelotti said on the post-match press conference.
Ancelotti then went on to explain his decision to make tactical changes early in the game, and stated he had no other choice following Caen's strong performance in midfield.
"The tactical change after 25 minutes had nothing to do with the understanding between [Guillaume] Hoarau and [Kevin] Gameiro. It was simply that Caen were putting us under a lot of pressure in midfield and we couldn't get the vertical passes up to our forwards," he said.
"The change allowed [Javier] Pastore to take his preferred attacking midfield position and eased the pressure on [Blaise] Matuidi and Thiago Motta."
PSG sit atop of the Ligue 1 table at the moment with 59 points from 28 games.