PARIS - Four-time Champions League winners Barcelona and French champions Paris Saint Germain suffered few problems in reaching the European Champions League quarter-finals. Barcelona - who had come into their game on the back of some poor league form - beat Manchester City, who had Pablo Zabaleta sent off, 2-1 for a 4-1 aggregate victory.While Barcelona's win saw them join domestic rivals Atletico Madrid in the last eight, City became the second English side in two nights to bow out, Arsenal having exited on Tuesday. Lionel Messi opened the scoring for Barca with his eighth Champions League goal of the campaign before Vincent Kompany levelled just before the final whistle.But there was still time for Dani Alves to strike the winner as Barcelona qualified for the quarter-finals for the seventh successive season. While victory will ease the pressure on Barcelona boss Gerardo Martino, defeat for City will increase demands for manager Manuel Pelligrini to deliver the Premier League title, as this latest setback came four days after they were knocked out of the domestic FA Cup by second tier Wigan.Barcelona forward Cesc Fabregas said that while others might be saying Barcelona were a shadow of previous sides, they were quite happy with how things were going. "Everything is good, it's not that bad," said the former Arsenal star."We're in the final of the Cup against Real, we're four points behind in the league. To be the Barcelona of two, three, four years ago is very difficult because they were probably the best team in the history of football. It's very difficult to maintain this level but we don't have to be the best (ever), we just try to stay at the top of our game." PSG, who Barcelona beat in last season's quarter-finals, kept alive their hopes of becoming only the second French side to win the trophy - after Marseilles in 1993 - with a 2-1 win over German outfit Bayer Leverkusen for a 6-1 aggregate win. Goals by Marquinhos and Ezequiel Lavezzi cancelled out Sidney Sam's sixth minute opener to give Laurent Blanc's side their sixth successive win in all competitions.Leverkusen - who came into the match on the back of a run of five defeats and one draw - missed a penalty through captain Simon Rolfes and, to round off a miserable experience, also ended the match with just 10 men as Emre Can was sent off for s second bookable offence. Leverkusen's Finnish coach Sami Hyypia, who also has had questions raised about his future because of the recent loss of form, tried to look at the positive side despite the overall score. "I'm feeling a bit sorry for the team that we didn't get anything from the game," said Hyypia. "The starting point was difficult after losing 4-0 at home but we can take a lot of confidence for the future."