MANCHESTER: Manchester City came from behind to make a winning start in Champions League Group C on Wednesday with a 3-1 victory over Porto at the Etihad Stadium. City had fallen behind to a fine 14th-minute solo strike from Luis Diaz but a Sergio Aguero penalty brought them level before second-half goals from Ilkay Gundogan and Ferran Torres secured the win. Pep Guardiola’s side, defeated in the quarter-finals last season, struggled to find their fluidity in the opening 45 minutes but as Porto tired after the break, City’s quality proved enough.