Seedorf insists Milan are capable of reaching the quarterfinals.
"I've often been in situations in which we're not the favourites, even in years in which we achieved important things," he told a Press conference.
"The favourites were and are Atletico Madrid. I think the two sides will play in a similar manner to the first leg.
"They have a narrow advantage - the game is open and I'm expecting changes with regards to the first leg.
"We have to fight as a team and play with our hearts tomorrow. These things come before the technical and tactical aspects.
"Our approach to tomorrow's match will be similar to the one in the first leg. We will be aggressive and try to score.
"Milan have a great history, and we have to honour the club and the shirt.
"I am doing this job with great enthusiasm and am confident that we can build a great future. And it is a future that won't change whatever tomorrow's result.
"The players are also extremely motivated. It's an important moment for everyone - we know we can write a beautiful page in this club's history."
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