Well that game at taht point was boiling so i can understand lippi letting him. He was our keyman on midfield and we could not afford to receive another goal.
That's not possible. All cards are cleared after the quarterfinals. Since you will get a one match ban after three yellow cards in Champions League, it's not possible to achieve this until the final, because there only the two semifinal games. As @Elvin pointed out, only a red card can get you a ban.