City had snatched two late goals to win the first leg 3-2 and they made the most of that fightback with a ruthless demolition job at the Etihad Stadium to clinch a 10-2 aggregate victory.
Aguero’s penalty opened the scoring at and the Argentine forward netted again before Leroy Sane, who also contributed three assists, struck against his former club.
Raheem Sterling, Bernardo Silva, Phil Foden and Gabriel Jesus all scored after the interval to complete City’s biggest home win in the Champions League.
Pep Guardiola’s side, who lifted the League Cup in February, remain on course for an unprecedented quadruple, sitting one point ahead of Liverpool at the top of the Premier League before this weekend’s FA Cup quarter-final at Swansea.
This emphatic victory was the joint-biggest ever Champions League knockout stage win but won’t linger long in the memory given Schalke’s total lack of resistence. However it could be a good omen as City beat Schalke en route to winning their only European trophy in the 1970 Cup Winners’ Cup.
Twice a Champions League winner as Barcelona boss, Guardiola claimed this week that City are “teenagers” in the competition compared to the more established European powers.
They have never won the Champions League, with their best performance a semi-final appearance in 2016 under Guardiola’s predecessor Manuel Pellegrini.
But City are one of the favourites to claim the trophy after Real Madrid and Paris Saint Germain crashed out and, on this evidence, Guardiola’s players are up for the challenge of showing they are more mature than he believes.
It seems only winning Europe’s elite club prize can make City fans fall in the love with the tournament.
Once again they loudly jeered the Champions League anthem, this time in frustration at UEFA’s recent investigation into the club over allegations of financial misconduct.
Guardiola had claimed it would be a “dangerous situation” to underestimate Schalke, but the struggling Bundesliga team were never a realistic candidate to spring a surprise.
– Floodgates opened –
Sprinting onto Kyle Walker’s pass, Sterling crossed for Aguero to shoot against a post in the opening moments.
Guardiola’s men monopolised possession and their territorial dominance finally paid off in the 35th minute.
Ilkay Gundogan clipped a pass into the Schalke penalty area and Jeffrey Bruma bundled over Bernardo, with the spot-kick awarded after being checked by VAR.
Aguero stepped up to nonchalantly chip the penalty down the middle as Ralf Fahrmann dived the wrong way.
Aguero has now scored in four successive Champions League games for the first time.
That opened the floodgates as Aguero quickly put the result beyond doubt three minutes later.
Sterling was the provider as he raced onto Gundogan’s pass and pulled the ball back to Aguero, who squeezed his shot past Fahrmann from a tight angle for his 27th goal of the season.
An interminable VAR delay of several minutes while Sterling was confirmed as onside drew more boos from City fans.
But they were celebrating again in the 42nd minute.
This time it was Sane who ripped open the shambolic Schalke defence, the German winger sent clear on goal by Oleksandr Zinchenko before driving a clinical strike into the far corner.
City were streets ahead of Schalke in every phase of the game and Sterling maintained his sublime form with a cool finish from Sane’s majestic pass in the 56th minute.
Bernardo made it five in the 71st minute, netting with a first-time shot from Sane’s pass.
There was still time for Foden to bag his first Champions League goal as the young midfielder took Sane’s pass and slotted home in the 78th minute.
Jesus beat Fahrmann’s weak attempted save with six minutes left to complete City’s perfect evening.
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