I don't see it as a must win. Cremonese and Empoli, and possible Udinese in the last round are the must wins. I think that we can survive with 1 point against Atalanta and Milan, and even with 0 points.
We have 5 pts advantage to Milan, Atalanta and Roma, with 15 pts to win till the end. If we win the three easy matches and win those 9 points, then all we'll need for top 4 is Milan and Roma not to win the last 5 and Atalanta not to win the last 4 matches.
If we do our job against the minnows, we're 99% sure of a top 4 finish imo. Especially considering the fact that Milan and Roma are still playing in Europe and they won't find it easy to rotate the squad and still win everything in Italy.
P.S: Unfortunately Allegri knows this too, so expect a horror performance from Juve in Bergamo.