It was a superb performance from Barcelona, and Lewandowski yesterday. Girona defeated Barcelona 4-1 last season on that same stadium when Girona was fucking hot. Things turned around for Barcelona this season and they were able to take their revenge. Barcelona next match with Atletico wouldn't be an easy one, because Atletico is only focused on Laliga and will take this match personal.
Barcelona are in their superb form and they are going to win Copa del Rey and La Liga as well as Champions League. It's only chance and Barcelona don't win any title in end of March, and the season is going with many matches for them to fight and win titles. Girona could not stop Barcelona but with remaining matches, Barcelona will likely lose points some times and Real Madrid if play well, will have opportunity to catch Barcelona.
In Copa del Rey, Barcelona will need to beat Atletico Madrid that nearly end their competition for La Liga title and will focus on Copa del Rey. So Atletico Madrid won't play weakly against Barcelona in Copa del Rey that is their only competition possible for winning.