Now in the US for the Club World Cup, Lautaro also welcomed new coach Cristian Chivu at Monday's media conference.
He said, "We have to turn the page and not think about what happened.
"I can't understand how it was possible to lose such a great opportunity in that way.
"I was sad, it was difficult to get to the bottom of the reasons, it took me 5-6 days to talk, I wanted to explain to my family. That night nothing was possible and they did everything: it wasn't us, we weren't a team. It's football.
"And now we have to move on, there is no other possibility, even if everything remains in my head."
Speaking with Chivu
Then he had his say on the arrival of Chivu.
"We spoke on the phone, even before finding him here. We spoke for a long time, he told me his ideas about work. And I like them, I agree with him, we think the same way.
"I understood and saw in him the desire to win, he is a man with the same mentality as me. It is important to breathe a bit of fresh air. It is nice to do different things with the new coach, even if the concepts are not that different from (Simone) Inzaghi."