Manchester City made a winning start to their 10th attempt at winning the Champions League after fighting back to beat Porto.
The Portuguese champions took a surprise early lead but Sergio Aguero quickly levelled from the spot and second-half goals from Ilkay Gundogan and substitute Ferran Torres gave City victory.
This was not a vintage performance from Pep Guardiola's side, who were sloppy at the back especially early on, but they were in full control by the time their opening game in Group C was over.
City had not even managed a shot at goal when they fell behind in the 14th minute, after a poor pass by Ruben Dias allowed Matheus Uribe to start a Porto attack.
Uribe found Colombian forward Luis Diaz, who was allowed to cut inside from the left and run virtually unchallenged into the City box before beating Ederson with a low shot.
City were not behind for long, however, with Aguero given the chance to equalise from the spot after Gundogan hit the post and Pepe clumsily took out Raheem Sterling as he chased the rebound.
Porto were unhappy with the decision, claiming Gundogan had stepped on goalkeeper Agustin Marchesin in the build-up, but the penalty stood and Aguero blasted home.
By now City were on top and Torres made certain of victory seconds after replacing Aguero, playing a neat one-two with fellow substitute Phil Foden and curling his shot home.
Meanwhile Champions League holders Bayern Munich extended their record run to 12 straight wins in the competition as they thumped Atletico Madrid.
Winger Kingsley Coman, matchwinner against Paris St-Germain in Lisbon at the end of August, scored in either half of a superb all-round display.
Midfielders Leon Goretzka and Corentin Tolisso also found the back of the net in a near-faultless performance from the German giants.
Only Real Madrid and AC Milan have retained the European Cup since Brian Clough's Nottingham Forest managed the feat in 1980, but few would back against a Bayern repeat this time around.
Bayern were already favourites with the bookmakers before this warning sign, which saw the holders rain in 16 efforts on goal.
Elsewhere Premier League champions Liverpool were helped by an own goal from Nicolas Tagliafico to get off to a winning start in the Champions League against Ajax.
Tagliafico sliced Sadio Mane's cross into his own net with 10 minutes of the first half remaining, moments after Liverpool keeper Adrian denied Quincy Promes from close range.
Liverpool's Fabinho then acrobatically cleared Dusan Tadic's lob off the line, before Davy Klaassen's powerful effort bounced off the inside of the post in the second half.
The Reds, who also face Atalanta and Midtjylland in Group D, were returning to Europe as English champions for the first time since 1984-85.
⏰ RESULTS ⏰— UEFA Champions League (@ChampionsLeague) October 21, 2020
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