It took the world champions till late in the second half when Messi teed up by Neymar to score past keeper Petr Cech for the first time in his career.
Messi, who netted four goals against the Gunners in 2010 and a double a year later in knockout round wins, doubled Barca’s lead seven minutes from time when he beat Cech with a penalty, having been tripped by Arsenal substitute Mathieu Flamini.
Arsenal relied on counter-attacks and had chances, most notably from Alex Oxlade-Chamberlain and Olivier Giroud, but just were not clinical enough in front of hoal. But now have a daunting task to turn the tie around in the Nou Camp.
Barca’s frontline of Luis Suarez, Messi and Neymar had scored 91 goals in all competitions this season but for the first 20 minutes they were subdued in an electric atmosphere.
Arsenal should have taken the lead midway through the first half when Hector Bellerin’s scuffed shot fell for Alex Oxlade-Chamberlain in front of goal but he scooped his effort straight at goalkeeper Marc-Andre ter Stegen.
Barcelona stepped up a gear in the second half and changed the game
Barcelona had two good chances with Suarez heading Dani Alves’s cross wide when he should have scored at the end of the opening period and Neymar was denied by Cech after being played in by Andres Iniesta.
Starved of the ball for long periods, when The Catalans were just trying to keep posession but Arsenal still posed a threat though and Ter Stegen did well to keep out Olivier Giroud’s close-range header from a Mesut Ozil cross.
With 19 minutes left Suarez and Neymar combined in devastating fashion and the Brazilian set up Messi who steadied himself and picked his spot to beat Cech.
Suarez then hit the post when he should have scored before Messi struck again, this time with a calmly struck penalty.
Leaving Arsenal a huge task in Spain.
Luis Enrique the Barcelona manager spoke after the game and said .
“We had a lot of possesion Arsenal tried to pressure in the second half but we raised our level we deserved to win. Every player gave 100%.
We were able to tackle all the problems they could present to us”.
Arsene Wenger speaking after the game
We are disappointed we allowed the first goal there was no excuse.
Barcelona are better than us but we could have won the game.My players put in a lot of energy tonight. We had chances to finish the game. Its a shame my players never got satisfaction from tonight they gave 100%.
Barcelona maybe the best team in the world but they can be beaten.