Not the most emphatic victory, perhaps, but undoubtedly one of the most impressive performances of recent times. The Villarreal win aside, City struggled away from home in the Champions League this season; form which has impacted on their play as a whole since returning to European competition on a consistent basis (note the unsuccessful return legs against Hamburg and Dinamo Kiev after poor results in the first leg away from home).
The win last night also come against one of Europe's most dominant sides at home. At The Dragao, Porto were previously seven games unbeaten in European competition and even more impressively are unbeaten dating back to 2008.
Being in the thick of a tight Premier League title race there were some questions as to how seriously Roberto Mancini would take the competition, particularly after dropping out of the Champions League, but the side he fielded last night was evidence enough (even allowing for the fact there is no league game this weekend) that City are serious about trying to win the competition. An important fact that shouldn't be overlooked is that as well as attempting to add some silverware is that the better City do in the Europa League this season the better their European ranking will be - important in wanting to avoid the potential pitfalls that being in Pot 3 of the Champions League draw can bring.
Porto displayed all the confidence runs of this nature inspire during a first half that saw them go in with a deserved 1-0 lead. The movement amongst their front players was excellent; pulling the City defence out of position and creating space for attacks and Varela stole in front of Gael Clichy to convert Hulk's cross past Joe Hart.
Where City lacked a little spark during the opening forty-five minutes were more purposeful in the second half. The returning Yaya Toure and Mario Balotelli looked more assured within the side and Samir Nasri - again excellent in terms of his passing efficiency and ability to create opportunities - came to the fore and far from buckling under pressure from the home side City were the side who were the most composed of the two and played their most ‘European' style of performance; patient in approach and unwilling to try and force situations. Even when trailing City (something City have done for just under 30% of the time in European games this season compared to under 3% of Premier League games) didn't chase the game and having got back on level terms visibly grew in confidence.
Taking the game back to The Etihad on level terms would have been considered a good result (and against the competition holders don't forget) but the late winner scored by Sergio Aguero to convert the burst forward from Yaya Toure was such a significant one. It of course means that not only do Porto have to win next week, but the reality is that City have the added cushion of knowing that even a 1-0 defeat will see them progress to face Legia Warsaw or Sporting Lisbon (who drew 2-2 in the first leg) in the last sixteen - a prospect that whilst by no means guaranteed is a far healthier position than previously enjoyed at the half way stages of European ties.