The loss saw the Blaugrana lose their Copa del Rey semi-final tie 4-2 on aggregate.
"We have to give more, we have to pick ourselves up, move forward and win on Saturday [against Real Madrid in La Liga]," he told Barca's official website after the game on Tuesday.
"We have to learn from this. The two most important titles (La Liga and the Champions League) are coming up and we have to move forward.
"We're a bit down but starting tomorrow we have to start working hard because we represent a very important institution."
Barcelona are currently 12 points clear at the top of La Liga.