Max Allegri explained how Frenkie de Jong and Ajax got away from the Juventus tactical trap. "We didn't create enough problems for them."
Cristiano Ronaldo's diving header was cancelled out by a David Neres strike within 40 seconds of the restart, so it all goes down to the second leg in Turin.
As Giorgio Chiellini and Emre Can were out injured, Daniele Rugani started in central defence.
"I was confident Rugani would do well, as he's one of the best defenders in Italy. He is extraordinary when defending, just needs to improve a little when building from the back," the Coach told Sky Sport Italia after the 1-1 draw in Amsterdam.
"Ajax are in the quarter-finals, pass it very well in tight spaces and push a lot of men forward, so of course they're dangerous opponents. They were pressing us hard and created spaces, but we didn't hit them on the counter as much as we should've done.
"I don't think we were distracted on the goal, but we did concede straight after the break and Ajax gained confidence, while we were a little in shock.
"I introduced more technically-gifted players, as it was time to work our way out of their pressing with more precision and technique.
"Ronaldo proved once again he is a player of a different level. His timing and movement is different to everyone else."
Rodrigo Bentancur was instrumental in the goal, as his run took away Matthijs de Ligt to create room for Cristiano Ronaldo's diving header.
"A midfielder needs to push forward too and create movement. Bentancur didn't do that against Milan on a Mattia De Sciglio cross, but he did this time and created the space for Ronaldo's run.
"Federico Bernardeschi and Blaise Matuidi had some good runs early on and Ajax go forward in so many that they leave few behind to defend, so we should've made more of those situations.
"Miralem Pjanic was very useful when helping the defence, but struggled a little more when it came to building the play out from midfield."
Allegri was asked why Frenkie De Jong had so much freedom to play in the Ajax midfield.
"Ajax usually move De Jong over to their left, our right, so Bernardeschi was meant to go and get him. He figured that out and wandered over to the other side, so one of our strikers had to pick him up. De Jong is where the Ajax moves start from.
"They had so many players on yellow cards, and are aggressive so make some risky tackles, but we didn't create enough problems for them with our through runs. Their central midfielder struggle and the goal came from an opening with Ronaldo through the middle, who then spread it wide and got on the end of the cross."