Milan will have a hard time against Fiorentina, but they will not lose. The league champion is now clear, but the competition with Juventus for the 2nd place continues.
My prediction is that Milan will win this game and keep the points difference with Juventus.
In week 30 almost every team has a tough opponent. That's one reason I like the Serie A. From the 1st position to the 9th positions are filled with teams that are very good and can win any team if paired together. The fact that one team is better than the other doesn't give them a chance to relax beyond they do they'll be stunned by what would happen to them.
Milan is currently in better form than Fiorentina and I believe Milan would win but they have to work extra hard to win. Milan wouldn't want to slip up and let Juventus overtake them and take the 2nd position from them.
Now, speaking of Juventus, they play Lazio who are not in a blistering form, but they also have the potential to win Juventus considering the fact that Juventus is having a poor run recently. Don't also forget that if Juventus loses and Bologna wins, the difference between them would be just a point, further jeopardizing Juventus's chances of playing in the Champions League.
Napoli is facing Atalanta. Both really need this win. if Napoli wins then they overtake Atalanta and go a place higher to 6th which would give them a chance to play in Europe while Atalanta wouldn't want that to happen because they're also fighting for a European football spot.