- Aguero scored his 150th Premier League goal in his 217th appearance - only Alan Shearer (212 games) has scored 150 in fewer games in Premier League history.
Post-match, however, City manager Pep Guardiola lamented their habit of conceding too many corners and revealed, who he believed, was the best corner kick taker in the league- Southampton's James Ward-Prowse.
Southampton had the minor consolation of becoming the first team in 630 minutes to score against City but the leaders' form is ominous for the rest of the division.
Guardiola confirmed that both Ilkay Gundogan and Nicolas Otamendi are available after recovering from knocks.
Aymeric Laporte is expected to start once again. Kyle Walker and Benjamin Mendy should continue as the full-backs.
Fernandinho is expected to anchor the midfield. When you attack good, you defend well.
Ivan Ordets, Maksym Malyshev and Fernando all look unlikely to feature for the visitors due to injury. City are now top of their group but a loss or a draw could see them relinquish that position. They create two versus ones in good areas.
That goal set the tone for the Saints, who were totally outclassed throughout.
GBI launches investigation into allegation of attempted election hack
A representative for the Department of Homeland Security confirmed the agency had been notified, but it deferred to Georgia officials for details.
Watford have been decent, but they were just beaten at Newcastle, and simply have to be dispatched at St Mary's for the sake of points, confidence and ending the long wait for a home win. Of course Manchester United is a big game but we can not start thinking about that until we have played Shakhtar.
Manchester City have kept eight clean sheets in their previous ten matches across all competitions.
Only teammate Sergio Aguero is level with Sterling on goal contributions this campaign having got on the scoresheet seven times while providing four assists.
"Last year was hard for me for many things".
They finally scored a goal, albeit from the penalty spot, to break their barren run.
Manchester City are playing with enormous confidence and swagger once again, as witnessed in their thrashing of Southampton this past weekend, with their attack firing on all cylinders.
Late on, Sane got amongst the goals to make it 6-1 for the Citizens after a superb, clinical display.
Given how easily Guardiola's side dispatched the Ukrainians last time out, we at The Hard Tackle expect them to walk away with another comfortable victory on Wednesday night and take a step closer towards qualification for the next round.