Having gone into the game 1-1 on aggregate, the Yellow Submarines are into the Champions League quarterfinals after the triumph.
"It is a joy to be among the top eight in Europe. And to do it away from home is a double satisfaction," smiled Pellegrini.
Asked about the goal scoring performance of Ariel Ibagaza, Pellegrini added: "There are always great individual performances, but I prefer to talk about the collective.
"I don't care who we draw for our next opponents as long as we maintain the level of the second half. All are difficult rivals."