A pair of Cristiano Ronaldo penalties, both awarded for handling offences, allowed Juve to grab a point.
“We were up against one of the form teams in Europe right now," Sarri told DAZN.
“They are aggressive, so organised, and at the start we made the mistake of wanting the ball passed to feet, but they pounce on these situations and it's how we conceded the goals, by losing the ball.
“Playing against Atalanta is very difficult. They seemed much sharper than us in the first half too, but we managed to get back into it and fortunately the second half was much better.
“We had conceded the second goal when we were taking control. We were more energetic, but compared to the first half, we defended much higher and weren't so passive. It allowed us to win back the ball more often in midfield and that's what changed the game."