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.
"If I'm being honest we are struggling at the moment," said German midfielder Gundogan.
"Fernandinho went off at the end, we have players playing in different positions. I am not 100% there because I had Covid, we are not all at the same moment.
"That is the challenge for this season, it's not going to end for a while" he added
Porto grabbed the lead when City's Ruben Dias, a recent signing from Benfica, gave away the ball and Colombian winger Diaz cut in from the left, burst diagonally across the City defence and shot into the far bottom corner of Ederson's goal.
The home side were soon back on level terms though when, after Gundogan had struck the post, Porto defender Pepe bundled over Raheem Sterling in the resulting scramble and Aguero converted the ensuing penalty.
City were far from their flowing best but went in front in the 65th minute with a perfect, curling free kick from Gundogan over the wall and beyond the reach of Porto keeper Agustin Marchesin.
Substitutes Torres and Phil Foden then combined to make it 3-1, with the Spaniard collecting a return pass from the England midfielder before gliding into space and driving a right-foot shot into the far corner.
City's Brazilian midfielder Fernandinho, brought on in the 85th minute, limped off in stoppage time with what appeared to be a muscle injury.
Porto remain without a win in 21 games in England, a run which has seen them manage just three draws.
(Reporting by Simon Evans; editing by Clare Fallon)
