Erling Haaland‘s goal after just five minutes proved enough to settle a frustrating game that the Blues dominated from start to finish, but could never quite put to bed.
City had chances to score more goals, but Saints defended stubbornly and in numbers throughout.
The victory takes the Blues above Liverpool to the summit of the Premier League, at least for 24 hours, as well as extending our unbeaten league run to 32.
What happened?
City wasted no time at all in exposing a fragile Southampton defence with a goal inside five minutes.
Bernardo played Matheus Nunes in behind the Saints’ defence and the Portuguese crossed into the six-yard box where Haaland wrestled in front of his marker to fire past Aaron Ramsdale and put the Blues 1-0 up.
It was Nunes’ fourth assist of the season - and all four have been for Haaland.
It was the Norwegian’s 14th goal of the campaign and ended a run of three Premier League games without a goal.
The next 20 minutes passed largely without incident and neither keeper was seriously tested.
Savinho was a box-of-tricks down the right flank, effortlessly gliding past Southampton defenders and on one occasion weaving through several challenges before being tackled as he was about to shoot.
All the while, just a goal behind, Southampton remained firmly in the contest.
Kovacic saw a snap shot scrambled clear by Ramsdale a minute before the break and Saints almost snatched an equaliser with the last action of the first 45 when Cameron Archer raced clear, only to see his rising shot hit the crossbar.
If City had needed a reminder that this game was far from over, that was surely it.
It had been a first-half that failed to ignite as expected after that early Haaland strike.
City came out looking energised and almost doubled the lead 25 seconds after the re-start.
Nice work by Savinho saw him cut inside on the halfway line before feeding Phil Foden who saw his low shot whistle a few inches past the right-hand post.
Three minutes later Haaland saw a header cleared off the line and then sent another headed effort straight at Ramsdale seconds later.
It seemed like the Blues were upping the ante and looking for what could potentially be a killer second goal as quickly as possible.
Then Savinho sent in a deliciously teasing cross to the far post only for Haaland to prod just wide.
City continued to dominate without testing Ramsdale too often.
Southampton packed their penalty area with 10 players whenever the Blues were attacked - which was for the majority of the half - before launching the occasional counter-attack.
It resulted in a tense last few minutes, with the visitors throwing caution to the wind in search of a shock equaliser that, thankfully, never came - or ever seemed looked likely to.
Saints, however, will take pride in a performance that suggested they will eventually pull away from the bottom three if today’s standards are maintained.
WATCH: City 1-0 Saints: Short highlights
Teams
CITY: Ederson, Lewis (Stones 90+7), Gvardiol, Dias (C), Akanji, Kovacic, Bernardo, Nunes (Gundogan 86), Foden, Savinho, Haaland
Subs: Ortega Moreno, Carson Ake, O’Reilly, McAtee
SOUTHAMPTON: Ramsdale, Walker-Peters, Harwood-Bellis, Bednarek, Stephens (C), Downes (Sulemana 87), Manning (Bree 76), Lallana (Aribo 60), Fernandes, Dibling (Armstrong 46), Archer (Onuachu 87)
Subs: McCarthy, Sugawara, Cornet, Ugochukwu
Attendance: 52,844
blues edging games - and doing enough
With a sizeable injury list side-lining six first team regulars, it is perhaps no surprise that City aren’t quite as free-flowing as normal.
It’s even harder to face teams who defend so deep and with so many bodies each week.
That said, with 22 shots - eight on target - the Blues will feel there were enough opportunities to have avoided the slightly nervy last few minutes.
But the fact is it is another three points on the board and breaking down packed defences week in, week out, is not easy to do.
With Spurs in the Carabao Cup followed by Bournemouth, Sporting Lisbon, Brighton and Spurs again. the regular low block we have faced so often recently might be something of a novelty the next time we face one!
What it means...
City are top of the Premier League with 23 points from 27 games.
Liverpool are a point behind with a game in hand - they face Arsenal tomorrow afternoon at the Emirates.
The Blues remain unbeaten this season and have now gone 32 Premier League games without loss.
What’s next?
City are next in action on Wednesday evening with a Carabao Cup 4th round tie away to Tottenham.
The game is on Wednesday 30 October and will kick-off at 20:15 (UK).
Then the Blues are on the road again, with a tricky-looking Premier League clash away to Bournemouth.
The match is on Saturday 2 November and will kick-off at 15:00.
STAR MAN
Savinho couldn’t have done much more in a game where he never stopped running or trying to find different ways past the Southampton defence.
Some of his trickery is exceptional, as is his speed and dribbling.
He will be disappointed not to have provided an assist or maybe got on the scoresheet, but it was an impressive 90 minutes nonetheless.
Honourable mentions too, for Bernardo and Mateo Kovacic who also worked tirelessly.
Pep reaction
“I prefer to be top than not being top, but it’s not the point. Look what happened today. Aston Villa dropped points and Brighton dropped points because it’s so difficult.
“We won at Wolves in minute 95. Today we created chances and we could have scored two or three goals, the expected goals is much better.
“But I have to admit it was a demanding game for us - such a demanding game for us.
“We ran incredibly today. We have to accept it and learn. I will watch it learn and maybe in the future we can use it.
“I learn a lot from other managers and if think there is a good idea. This is going to happen.”
BERNARDO reaction
“We have a lot of respect for all the teams in the Premier League. These guys we played today, I watched some of the games they played in the season and I think they deserve a lot more points than what they’ve got. A lot of respect for the way they play.
“They press high, they try to build up with the ball. It makes it very difficult to press them because if you go man-to-man in the middle they find the space, then it’s not easy for our defenders and they have fast guys up front. Tough game for us but very happy with the three points.
“Now, we’re used to that when teams defend deep against us which makes it more difficult, we have to be patient. We are used to that. We had our chances to score three or four goals to make it, but they deserve a lot of credit for what they did here today.”
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