The first-leg will be staged in Eindhoven tonight.
"I remember when we went to PSV and signed Ruud Gullit," said Galliani. "They are a noble side who have had players such as Ronaldo and Romario in their ranks.
"It is one of the most important play-off games, but let us not overload it. These games are vital every year, but it is not the most important in our history.
"We played well on our American tour," Galliani added. "I think the side is in good shape, but I don't want to make any predictions "
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