Match ends, Manchester City 1, Steaua Bucharest 0.
Joe Hart marked his first start of the season, and possibly his last for Manchester City, with a clean sheet as Pep Guardiola's side advanced to the Champions League group stage.
Keeper Hart, who is expected to leave with Claudio Bravo close to signing, was rarely troubled after being made captain against Steaua Bucharest.
Leading 5-0 from the first leg, City rested several key players.
Fabian Delph's header from Jesus Navas' cross made it 6-0 on aggregate.
Say hello, wave goodbye
Hart was dropped for City's first three games as Guardiola opted for Willy Caballero instead.
However, the City boss had hinted at his pre-match news conference that Hart would start this one - and he gave the 29-year-old the added responsibility of leading the team out.
Hart's every touch was applauded by home supporters while there were many banners on display in support of the England keeper.
In the 66th minute of his 348th start for the club, while a Steaua Bucharest player was receiving treatment, the Etihad reverberated to chants of "Stand up if you love Joe Hart". He responded by shaking his head and touching the club badge on his shirt.
Hart had little to do as the visitors sat back. He produced a couple of examples of short, sharp distribution with his feet - contrary to the perceived weakness that may have counted against him under Guardiola - while making two saves to keep out substitute Nicolae Stanciu's free-kick and then blocking Alexandru Tudorie's effort.
He also celebrated Delph's goal by raising both arms and punching the air.
At the final whistle, Hart applauded all four sides of the Etihad along with his team-mates.
Concern for Iheanacho
As well as Hart, there were four other first starts of the season for City players - including a first competitive start for 19-year-old right-back Pablo Maffeo - as Steaua embarked on the improbable task of turning over a five-goal deficit.
Yaya Toure, who is also expected to leave next week, hit the side netting, Nolito volleyed at the keeper and young forward Kelechi Iheanacho forced a save before Delph's well-executed header following the best move of the game.
Guardiola was at his animated best throughout - conducting mini-tutorials, calling Maffeo, then John Stones over to the touchline for one-on-one instruction.
Despite City's victory, there was one moment of concern for Guardiola when Iheanacho was carried off on a stretcher after pulling up and receiving swift medical treatment.
That raises the possibility of a reprieve for fellow striker Wilfried Bony, who has been linked with West Ham and was not in the 18-man squad on Wednesday.
Who could City face in group stage?
City are in Thursday's draw for the Champions League group stage along with four other British teams - Leicester City, Arsenal, Tottenham and Celtic.
No team can play a club from their own association.
Guardiola could find himself up against one of his former clubs - Barcelona or Bayern Munich who are both in Pot 1 along with holders Real Madrid, Juventus, Benfica, Paris St-Germain and CSKA Moscow.
All will become clear around 17:00 BST.
Man of the Match - John Stones (Man City)
What they said
Manchester City manager Pep Guardiola: "We are ready for the Champions League. The players and club deserve it. We were the better team.
"It was not easy with 10 players behind the ball but in the second half we adjusted and attacked much better. The spirit was amazing. Now is a day to celebrate our qualification for the Champions League."
Regular forwards Sergio Aguero and David Silva, both unused substitutes here, are expected to return for Sunday's Premier League home game against West Ham United (16:00 BST).
- 24StonesSubstituted forTosinat 60'minutes
- 9NolitoSubstituted forAngelinoat 60'minutes
- 42Y Touré
- 72IheanachoSubstituted forFernandinhoat 76'minutes
- 19AganovicSubstituted forStanciuat 53'minutes
- 11MuniruSubstituted forAchimat 62'minutes
- 23PopescuSubstituted forPopaat 53'minutes
- Pawel Gil
- Shots on Target
Second Half ends, Manchester City 1, Steaua Bucharest 0.
Offside, Manchester City. Fabian Delph tries a through ball, but Angelino is caught offside.
Angelino (Manchester City) wins a free kick in the defensive half.
Foul by Gabriel Enache (Steaua Bucharest).
Corner, Steaua Bucharest. Conceded by Pablo Maffeo.
Attempt missed. Jugurtha Hamroun (Steaua Bucharest) right footed shot from outside the box misses to the right following a set piece situation.
Foul by Aleksandar Kolarov (Manchester City).
Nicolae Stanciu (Steaua Bucharest) wins a free kick on the right wing.
Foul by Fernandinho (Manchester City).
Marko Momcilovic (Steaua Bucharest) wins a free kick in the defensive half.
Delay over. They are ready to continue.
Substitution, Manchester City. Fernandinho replaces Kelechi Iheanacho because of an injury.
Delay in match Kelechi Iheanacho (Manchester City) because of an injury.
Foul by Jesús Navas (Manchester City).
Jugurtha Hamroun (Steaua Bucharest) wins a free kick in the defensive half.
Attempt saved. Alexandru Tudorie (Steaua Bucharest) left footed shot from the right side of the six yard box is saved in the bottom right corner. Assisted by Bogdan Mitrea.
Corner, Steaua Bucharest. Conceded by Joe Hart.
Attempt saved. Nicolae Stanciu (Steaua Bucharest) right footed shot from a difficult angle and long range on the left is saved in the top centre of the goal. Assisted by Alexandru Bourceanu.
Foul by Jesús Navas (Manchester City).