Ferran Torres brought the game to life after a goalless first half, continuing an impressive vein of form in Europe's top competition with a smart 48th-minute finish.

Aguero, who has struggled with the after-effects of meniscus surgery over the early months of the season, came off the bench to seal the points 13 minutes from time, offering Pep Guardiola a timely reminder of his qualities ahead of Sunday's Manchester derby at Old Trafford.

Another substitute, Raheem Sterling, completed the scoring for City, who were already through as group winners and can now boast their best-ever Champions League haul of 16 points.

Marseille bows out of continental competition in 2020-2021 after five defeats from six outings.

Ilkay Gundogan delivered a wonderful out-swinging free-kick from the right in the 13th minute and Aymeric Laporte should probably have done better than heading over under pressure from Alvaro.

Marseille grew into the contest and, shortly after Eric Garcia's knee injury forced City into a defensive change, Dimitri Payet had a deft finish with the outside of his right foot ruled out for a clear offside.

Garcia's replacement, John Stones, made a vital sliding challenge to deny Valere Germain after Florian Thauvin skipped past Nathan Ake with ease.

Guardiola's attacking half-time change, which saw Sterling replace Gundogan and Bernardo Silva and Phil Foden drop into central attacking midfield positions, paid swift dividends.

Silva drove forward after picking up Stones' pass to play in Mahrez, who laid on Torres for a composed close-range conversion.

Foden twice went close before the hour - scuffing wide on the end of a move he started before shooting too close to Steve Mandanda, who kept out a stinging 65th-minute drive from Kyle Walker.

Torres was unable to convert the rebound on that occasion but Mandanda must have know what was to follow when he parried Ake's firm header from Foden's corner and saw the arch poacher Aguero lurking.

It was Sterling's turn to smuggle the ball home in the final minute when the unfortunate Mandanda could only push Torres' cross onto Alvaro.