"With Leo playing in his element we have taken the first step and now we move onto the second," said Enrique.

"It is clear that Messi is the best player in the world. He has a unique quality that it is easy to see. Giving assists, scoring goals, pressing, defending, he does everything."

Messi opened the scoring three minutes before half-time with a trademark left-footed finish, but the hosts briefly looked in trouble when Jaiver Mascherano was sent-off for denying a clear goalscoring opportunity moments later.

However, any Barca nerves were settled just a minute into the second-half as Munir El Haddadi doubled their advantage on his senior debut and Messi classily rolled home his second of the game just after the hour mark to round off the scoring.

"If he wanted Messi could be the best defender in the world. We see him do even more difficult things in training against high quality opponents in his teammates," Enrique added.

"He has a magic wand and he will continue being the best in the world as long as he wants."

Big money summer signings Claudio Bravo, Jeremy Mathieu and Ivan Rakitic were also making their Barca debuts, but it was their latest wonderkid from the La Masia academy Munir who stole the show.

"I am very happy to have made my debut and that the team won the game," he said.

"It is an honour for me to score here at the Camp Nou with these players like Messi and score a goal."

The 18-year-old owed his chance to the absence of the injured Neymar and suspended Luis Suarez and showed he could be an important player this season as he smacked an effort of the bar in the first-half before sealing a fine individual display with a lofted finish from Rakitic's through ball.

"I had no fear about playing him," said Enrique.

"He trains like he plays and gives us a lot of options. He shows great personality and he never rests.

"Let's not exaggerate he still has a lot to do to become a first team regular at a club the size of Barcelona, but his progress leads us to have great expectations for him."