Leao returned to the starting XI and was man-of-the-match in their Champions League win at Real Madrid.
At today's Cagliari preview, Fonseca discussed his management of the Portugal attacker.
How important is it not to ruin the Madrid result tomorrow in Cagliari?
"It's important to keep in mind the good things we've done, but it's also important to understand that in Cagliari it will be a different game. We have to be a different team to be able to play against Cagliari. It will be a totally different game. Since Wednesday I've stopped thinking about Madrid to think about Cagliari: we need the right attitude to win tomorrow."
Is it possible that Madrid will change the team's mindset?
"Even before the Madrid game, the team was aware of what it could be. It's true that the victory against Real gives the players more confidence, but all the games are important. I don't think the game against Real is more important than the one against Cagliari. We have to get back to the championship now, which is different."
Musah wide a one shot option?
"It was a strategy for Madrid. I don't know if we can do it in other games. Maybe yes, maybe even with other players... But it was mainly a strategy for Madrid, for the characteristics of the Real players."
How is Alvaro Morata?
"It was a strange situation: in a drill yesterday he collided with Pavlovic. Initially I didn't think it was a problem like the one that later turned out to be, but he's not ready to play tomorrow. He's fine, but he's not ready."
Morata said that Leao must understand that he can make football history...
"Leao will be a starter tomorrow. I said after Madrid that he can do even better, especially in certain situations. We must all understand that tomorrow will be a totally different match, especially for Leao, with individual marking and without all the space he had against Real. But I expect Rafa to be at the same level."
Do you also expect a few more goals from Leao?
"Leao had situations in the last 30 meters of one-on-one, he had nine, ten... He can improve in the last choice. It is clear to everyone that he can also improve defensively. We must continue to work with him to make him improve on these issues, which are important both for him and for the team."
Tomorrow is important to get back to the top of the table?
"It's important for everything. We can't lose points. This victory over Real makes no sense if we don't win against Cagliari. However, it will be a totally different match."
What is your relationship with Leao?
"Good and has always been good. I can't say everything. Every coach has a strategy. I tried to have a strategy with Rafa, maybe it wasn't the best, then I tried another one and it seems to have had some effect... I've never had problems with Rafa. He accepted the situation well and had the reaction I wanted. I expect Rafa to continue like this. If this is the solution, maybe we can see Rafa more often on the bench (laughs)..."
How do you explain that in the two most difficult matches you showed your best version?
"There are several explanations. First: these types of matches are a great motivation for the players; the players face these matches with more motivation than in other matches. And this is the reason why I am more worried about playing against Cagliari than against Real. Second: they are totally different matches. When you play against teams like Real, what you must not do is not have courage, because these teams give you space, you can play, you can control the match and this brings confidence. Sometimes it is more difficult to play against Monza or Cagliari than against Real Madrid. Against Real, we have space to play. Tomorrow I am sure we will not have the same space to play."
Do the fans love you more after Madrid?
"It's normal (laughs). But for me nothing has changed. I have to follow the path I believe in, I have to always be balanced. I'm not someone who watches everything when I win, and when I lose I don't watch anything. I'm always the same: I don't watch anything."
Do you feel like you have a cup team rather than a championship team? Can you win the Champions League?
"I haven't thought about that. I like it, yes, but I also like that the team understands that the championship is the priority. We must have the same courage to win games here. Serie A is our priority."
The Spain coach said that Morata will play for the national team...
"I don't know why he said that. There is a protocol that says a player must stop for 10 days. I don't know how he can say he'll play. I know he can't do anything. I mean, it's not an option, it's mandatory. I don't know how de la Fuente can do this."
Tomorrow we need to change to win?
"If you give me some advice, maybe I'll follow it. Three midfielders? But we already play with three midfielders. In Madrid we put four."
Is it the right nastiness that makes the difference?
"We didn't agree with Monza's assessments. But I saw the right attitude in Monza, because we faced other difficulties with the right nastiness and the right head. I expect it to be the same tomorrow. Stuttgart had the right attitude against Atalanta, but they found it difficult to face a team that defends in that way. As a coach I know that it is very difficult to face teams that defend like that."