Biggest game is against Spurs. A loss tonight would mean that we are 2 points (worst case scenario) away from top 4 with 17 games left to play. Scudetto is officially gone, so top 4 is our only objective. And we need to beat 2 of Roma, Lazio and Atalanta. If we can't do it, not only Pioli, but Maldini, Massara and every other person involved in the decision making of the club during the past 2 years should be kicked out.
The tie against Spurs, however, could change the whole season. In the 1/4 finals there will be some beatable teams. A semi final is an actual possibility if we start playing football.