Gerard Pique's goal secured the points on the opening night of Group F action, but Enrique remained tight-lipped when questioned whether he was concerned about the struggles they faced at the Camp Nou.
"I am sure that we will succeed with the help of all players," the Spaniard told reporters. "We have to analyse why the match was so difficult for us today.
"The players are not machines. Players need to be fit, but we have to improve."
Barcelona return to action against Levante in La Liga on Sunday night.