The Argentina international said: "Against Arsenal it was a good win and we will enjoy this moment because we know how difficult winning at this level is, so we are very happy now.
"The quarter-finals were two very difficult matches. In the first 20 minutes here we were no good, bad, but we came back well.
"They could play how they wanted to, but after Sami Hyypia's goal it was very good for us and the game changed then.
"In the second half, we could play how we wanted to and score how we wanted to.
"As for me, I know I made a mistake against Manchester United with the red card, so now I will try to concentrate on the Champions League.
"For this week, it has been the only competition in which I have been allowed to play in."