Stefan Ortega
Good save to deny Djenepo early on but was poor in possession in the build-up to Southampton's first goal through Mara, and was in no-man's-land for Djenepo's second to get lobbed from 30 yards. Not a good night for the City cup keeper. 4
Kyle Walker
A shaky start at centre-back, and lost Mara for the first goal. His half-time substitution was more to do with City's uneven formation, but he perhaps symbolises another Guardiola formation experiment in the space of a week that simply didn't work. 5
Aymeric Laporte
Bailed out Gomez to stop Djenepo getting a shot away early on, but couldn't cover him for the first goal. The best of City's defenders, in the opening 45 but that's not much of a compliment. Far more assured alongside Akanji after the break. 6
ALSO READ: Southampton vs City - as it happened
Joao Cancelo
Looked more comfortable on the right than recent games there, but struggled to influence either City's defensive or attacking play on a disjointed night. Another who improved drastically in the second half. 6
Sergio Gomez
Given the inverted full-back role into midfield but Southampton targeted him early on and after two big warnings he was guilty of giving away the ball for the first goal. A foul throw summed up a hopeless evening - and maybe one of his last guaranteed starts with Arsenal awaiting in the FA Cup. Replaced at half-time to ironic cheers from the away end. 3
Kalvin Phillips
In his eagerly-anticipated first start for City, Phillips looked a little panicky in possession and lacked the decisiveness of Rodri at times. Targeted by the Southampton press, Phillips looked vulnerable - as shown by his ponderous play in both first half goals - but he did improve after the break with a better system and better players around him. He will have hoped for more from his full debut, though. 4
Ilkay Gundogan
Should have done better with his early effort, and wasn't able to lead his side back into the contest at 2-0 down as the most senior player on the pitch before reinforcements arrived. 5
Phil Foden
Playing through the middle again, but with Southampton pushing so high, Foden got few chances to get involved and struggled to link midfield to attack. He may be able to grow into the midfield role when City have the ball, however he was anonymous when Southampton took the initiative and led the press from the front. Switched to the wing, he showed why his immediate future lies out wide. 6
Cole Palmer
Switched to the right-wing, Palmer did well to set up Gundogan early on, but found it hard when Saints took the lead. When City needed the ball to stick up front to relieve pressure, Palmer was too easily knocked off the ball. Replaced at half-time. 5
Jack Grealish
Better at keeping possession, and one of the only City attackers to run at his defender. Ultimately, though, he was another who left the gap between defence and attack too open for Southampton to exploit. Replaced for Haaland after getting away with an off-the-ball collision. 5
Julian Alvarez
Barely touched the ball in the first half, through either a lack of service or a good marking job by the Southampton defence. Dragged an effort wide at the start of the second half, and one cross just evaded him. Otherwise too quiet. 5
Subs
Nathan Ake (on 45)
Immediately strengthened the left side, and Saints had no joy down their right in the second half. He may be emerging as City's strongest left-back on recent showings, and should start there in the derby. 6
Manuel Akanji (on 45)
Another who improved the back line simply by coming on in his natural position. His derby chances have also strengthened just by not playing in that awful first half. 6
Kevin De Bruyne (on 45)
Instantly set the tone for the second half with a through-ball for Alvarez, and all of City's attacks came through him. It just wasn't enough. 6
Erling Haaland (on 55)
Added more of a focal point to City's attack, but couldn't get his side back in the game. 5
Rodri (on 62)
Brought on to replace Phillips for the final half hour. Solid as ever, even if his attacking colleagues couldn't take advantage. 6
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