MANCHESTER, England -- Barcelona outclassed 10-man Manchester City in the Champions League round of 16 on Tuesday, with Lionel Messi netting from the penalty spot in a 2-0 first-leg victory.

The Argentina forward scored his 25th goal in 27 games in the 54th minute, but despite its man advantage, Barca couldn't score again until the 90th through Dani Alves.

"We had a point to prove, and we did it very well," Barcelona midfielder Cesc Fabregas said, referring to previous criticism of the team.

It was an unsettling introduction to the knockout phase of the competition for City, with Barcelona's poise and panache enabling the four-time European champions to remain in near-complete control against England's emerging force.

City had managed to repel the waves of attacks by the Spanish champions until the start of the second half when Martin Demichelis couldn't keep up with the speedy Messi, dragging down his fellow Argentine and conceding the penalty.

Even after Messi made it 11 goals in 11 games since returning from injury, City managed to unsettle Barcelona goalkeeper Victor Valdes more than had it with a full complement of players.

But City couldn't grab an equalizer against the run of play, and Barcelona ensured it would win in Manchester for the first time when Dani Alves successfully completed a one-two with substitute Neymar to score the team's 113th goal of the season.

Barcelona's victory margin wasn't as great as the one secured by Paris Saint-Germain in the night's other first-leg. Zlatan Ibrahimovic scored twice as Bayer Leverkusen, like City, was reduced to 10 men -- and beaten 4-0.

City, playing in the third tier of English football 15 years ago, was in unknown territory at the Etihad. Against a team that has won the competition three times in the last eight years alone, City was in the knockout phase for the first time and playing the Catalan giants for the first time in a competitive fixture.

It showed, with Manuel Pellegrini's side struggling from the start to disrupt the visitors' flowing passing moves.

"If we don't have the ball it's just pointless to turn up," Barcelona coach Gerardo Martino said on the eve of the game.

City struggled to get a touch of the ball in the early stages. But the hosts emerged unscathed from its hesitant start and produced the first meaningful shot of the match after 25 minutes when Alvaro Negredo curled the ball at Valdes after a dithering defence failed to clear.

City goalkeeper Joe Hart had little to do, despite Barca's control, until he pushed Xavi's long-range strike high into the air.

It had been a quiet night for Messi until making his key contribution after the break.

When Demichelis brought him down, the initial contact appeared to have been made just outside the area, but the foul continued into the penalty area. And in front of the small contingent of visiting fans, Messi dispatched the spotkick past Hart.

It was Messi's first away goal against an English club and his 66th in the Champions League, putting him just five from levelling Raul's record.

Aside from Xavi firing over and Dani Alves skewing another effort wide, City looked more likely to find the net at times in the second half despite chasing shadows for most of the time.

Samir Nasri had a shot blocked by Sergio Busquets and, when David Silva brought down Pablo Zabeleta's cross and unleashed a volley but it went straight at Valdes.

Then a lightening move down the right flank was completed by Dani Alves, giving Barca a comfortable lead as it chases a first European title since 2011.