Milan face PSV in the first-leg tonight.
"Beating PSV is critical to the rest of our season," he told a Press conference.
"We must do everything possible to be in the next round of the Champions League.
"And I think my boys can succeed.
"I believe by October we'll have a better idea of how we're doing. For now we just have to focus on the upcoming games.
"We want to start well in the League against Verona.
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