But Gomes and Messi both got their second goals of the evening either side of the hour mark to put the game to bed and Paco Alcacer and Javier Mascherano, the latter from the penalty spot, quickly added gloss to the scoreline with just 67 minutes on the clock.
Alcacer became the third player to net a double with four minutes remaining to cap an emphatic scoreline to further increase confidence on the back of the El Clasico win at the Bernabeu.
"This is going to improve Paco Alcacer and Andre Gomes' confidence," said Barca coach Luis Enrique.
Mascherano scored his first goal for the club at the 319th time of asking and it clearly delighted everyone at the club.
"It is an anecdote that a player like Mascherano had not scored a goal," he said.
"He is a top player, his performance is beyond doubt, he is a born competitor who makes his team better."