The north London side managed to keep Barcelona at bay in the first half despite the visitors finishing with 71 per cent possession after the opening 45 minutes.
Olivier Giroud and Alex Oxlade-Chamberlain had chances to make the breakthrough for the hosts before Barcelona finally opened the scoring in the 71st minute.
Luis Suarez and Neymar combined on the left wing and Lionel Messi finished from close range with the Arsenal defence out of position.
Substitute Mathieu Flamini brought down the Argentina international with seven minutes remaining and Messi finished from the spot to seal a 2-0 first-leg win.
And Nicholas delivered his thoughts on Arsenal’s performance ahead of their clash against Manchester United on Sunday.
“The disappointing thing tonight is Arsenal did have chances but they didn’t take any of them,” Nicholas told Sky Sports.
“However, sometimes you have to hold your hands up. If they are a better team you have to accept it and that’s what they are, they are a better passing team, they are a better attacking team and with the three up front, no-one can live with them.
“Enjoy Messi, enjoy Suarez and enjoy Neymar. For the love of football, they are geniuses to watch.”
The north London side make the return trip to Barcelona on 16 March.
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