The Sky Blues failed to slice open the Saints defence after their enthralling mid-week over RB Leipzig in the Champions League.
City came close to snatching a late winner through Phil Foden, but the youngster's finish was ruled out for offside, as Pep Guardiola's side failed to find a way through the Southampton backline.
Here's how the City players fared at the Etihad Stadium:
Ederson - 6/10
Had to be on his toes several times throughout the clash, and tried to help build up play from the back.
Kyle Walker - 6/10
Was solid as ever for a large part of the tie, and his challenge that awarded the opposition a late penalty was overturned, as was his red card.
Ruben Dias - 7/10
The UEFA Defender of the Year commanded the City defence, as he made a series of crucial tackles and interceptions to deny Southampton any half-decent chances to score.
Nathan Ake - 7/10
Started his second game in the space of four days, and was composed as ever as he rose to the challenge amid what is a difficult time for the Dutch international personally.
Joao Cancelo - 7.5/10
The 27-year-old was at his creative best as he tried to influence proceedings by playing a couple of delightful balls in space for Bernardo Silva and Jack Grealish.
Bernardo Silva - 7/10
His work-rate was on point today as he led the press from the front by running across the pitch. Has made an incredible start to the season.
Fernandinho - 5/10
Struggled to deny the Saints on the counter at times, but he was pivotal to keeping the door shut when the visitors were having a positive spell towards the end of the clash.
Ilkay Gundogan - 5/10
He's had better games for City, as the German gave away the ball far too often, and was far from his calm, precise best that has made him such am important figure for Guardiola.
Gabriel Jesus - 6/10
He had everything apart from the end-product as he sparked a few brilliant bits of play down the right flank, but his crosses into the box were cleared by the Southampton centre-halves more often that not.
Raheem Sterling - 5/10
Handed his first start in five games, the England international struggled to make an impact against one of his favourite sides to play against, as he was positioned down the middle by Guardiola, who could drop him for City's upcoming games against Chelsea and PSG.
Jack Grealish - 7/10
He was City's most dangerous player throughout, as the former Villa man tried to take matters into his own hands by driving with the ball towards the Saints defence, who deserve their share of credit for keeping the door shut against one of the most potent attacks in the division.
Substitutes-
Phil Foden - 6/10
The Stockport-born midfielder nearly won the points for his side on the stroke of full-time, but despite his strike being ruled out for offside, he did speed up the pace in attack after his introduction.
Riyad Mahrez - 5.5/10
The Algerian hardly got a foot in the game, and was barely involved in attack after coming off the bench.
Kevin De Bruyne - 6/10
Was City's focal point in attack as soon as he was introduced, but he squandered late chance to bag the winner following a brilliant team-move.
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