The 23-year-old is yet to find the back of the net in six appearances for the Catalan club, however, and drew another blank in Saturday's 4-0 win over Deportivo La Coruna in the league.
It had been claimed that Enrique was already losing faith in the striker, but the Barcelona boss has given his full support to Alcacer, who scored 15 times for Valencia last season.
"Alcacer? We all know that strikers want to score goals, but it's true that against Depor he had no luck. What reassures me is that in training he scores goals and in games he gets many chances," Enrique told reporters.
"I'm sure he'll score many goals for Barcelona, but it's clear that he's finding it hard at first, as did Luis Suarez. The support from the stands encouraged him at all times."
Barcelona will return to Champions League action at home to Manchester City on Wednesday night.