Inspired by brilliant performances from Raheem Sterling and Sergio Aguero, City piled misery on Mark Hughes’ struggling visitors with a ruthless, free-scoring display.
Guardiola, however, was not fully satisfied with what he saw from his players and was particularly critical of his side’s defending in his post-match press conference.
Southampton were momentarily allowed a route back into the game when Danny Ings converted a first-half penalty after being tripped in the area by goalkeeper Ederson.
“We were lucky to score the fourth goal at the last minute of the first half because I had the feeling the game was not over,” Guardiola said, referring to Sterling’s first of two goals, which re-established City’s three-goal lead on the cusp of half time.
“We played with the ball so good but not without the ball. We were not stable behind. We concede a lot of corner kicks and with the best taker in the league [James Ward-Prowse] like Southampton had.
“The teams showed me some signals that in some positions we are not stable enough,” he reiterated.
When asked to expand why he thought City were not stable, Guardiola claimed Southampton were granted too many opportunities to score despite City’s dominance of possession.
“When they were close to our box, [we had] the feeling they can score goals,” he said. “When we had that feeling it’s not good.
“We can improve and that is good. I like to have that feeling that we won 6-1 and are top but at the same time we have to improve in many situations to be a more stable team because when we arrive in the next steps of the Champions League, when you concede in those situations you are out because the level is higher.”
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