Cocu admits his team face a huge test.
"We will fight with all our strength to win," he told a Press conference. "But for us, Milan will be a litmus test.
"We want to play big clubs, and this match is a huge opportunity for us.
"I have seen a lot of their games and I know they have a lot of quality.
"It is not going to be easy for us to deal with them. We need to reduce the amount of errors we make."
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