City needed only five minutes to take the lead against Southampton, Wesley Hoedt putting through his own net following a neat move involving Aguero, David Silva and Leroy Sane. It doesn't matter who plays, they know that.
To top off a insane few minutes at the Etihad, Pep Guardiola personally told the fourth official that Sterling had fallen over in the box.
Sterling did in the 67th minute when he latched onto Aguero's perfectly-weighted pass to score his second goal of the afternoon.
Hoffenheim's 2-2 draw at Lyon delayed City's progress, but they now sit three points clear of the Ligue 1 club at the top of the group.
The game was virtually over by the 18th minute when Sterling's cross from the right eventually found David Silva whose left-foot drive flew past the helpless Alex McCarthy.More news: India vs West Indies, 1st T20I
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Southampton did at least manage to register their presence as Ings earned a penalty after racing through and being clipped by City goalkeeper Ederson.
Jesus ruthlessly dispatched the penalty but will perhaps blame his failure to convert a glorious one-on-one opportunity soon after on a sudden pang of sympathy for the visitors.
It did little to change the complexion of the game, however, and Southampton had to scramble to deny Aguero, Sterling and Sane shooting opportunities as the hosts teased their opponents with some intricate passing. Not just with the ball. The England man scuffed his first effort but calmly stroked home at the second attempt after the ball rebounded off Ryan Bertrand.
On Wednesday night Manchester City's game with Shakhtar Donetsk proved it can't come soon enough as two of the officials somehow didn't spot that it was the ground that tripped Raheem Sterling and not an opposition player. A factor which could've hurt them, especially with James Ward-Prowse on set-piece duty.
And replays showed just what an very bad decision is really was.
And at half time of Manchester United's game with Juventus, which was goalless, Gary Lineker had to make viewers aware of the incident in the other match.