The two clubs were paired this morning in the round of 16 draw.
Deco said afterwards: "Playing the second leg at home is an advantage, but only if you approach the first match with seriousness. It's a very tough pitch; we won, but we suffered.
"This level is tough. People have their opinions and they know how difficult the clubs are, but it's a tough draw for everyone. Now we have to prepare for the next match."
The winner will meet the winner between Tottenham and Atletico Madrid in the quarterfinal.
On the prospect of facing Atletico, Deco said: "It's definitely possible.
"We have the second leg of our Copa del Rey tie and a league match; that would be four games, plus the ones we've already played. I don't know when was the last time we faced each other so many times in a single season."