The Gunners host Rafa Benitez's side in the first leg of their UEFA Champions League quarter-final on Wednesday, before a Premier League encounter at the Emirates on Saturday precedes the second leg of the European tie at Anfield.
"I think the confidence has been restored after a victory like this," the Frenchman told Arsenal TV.
"Maybe something has come back to us and we have to keep it.
"The next game is against Liverpool in another competition, but we know we can do what the boss will ask. We know it will be difficult, but we have to keep it going. We are back on track.
"I think we need to relax with our families and will think about the next game on Wednesday.
"We played with ten men and we need to relax. I go back to see my family and play with my son. I will eat the good food and everyone will be ready."