The England international was handed his first start since Manchester City's 1-0 defeat away at Tottenham on the opening day of the Premier League campaign back in August.
With Ferran Torres named amongst the substitutes on Saturday afternoon, the 26-year-old winger was positioned through the middle, with Jack Grealish and Gabriel Jesus on either side.
However, despite his impressive goalscoring tally since his arrival at the club in the summer of 2015, Raheem Sterling failed to influence proceedings against the Saints, who let Manchester City register just one shot on target throughout the clash.
Ahead of Manchester City's Carabao Cup third-round tie against Wycombe Wanderers on Tuesday night, Guardiola delivered his honest verdict on Sterling's performance against Ralph Hasenhüttl's side at the Etihad.
"He (Sterling) was so active in terms of movement, but football depends a lot on how good we do the process in build-up," said the 50-year-old in his post-match press-conference.
"And when it (build-up) happens, our strikers and wingers play better, and our attacking midfielders play better."
After an indifferent end to the 2020/21 campaign where he lost his place in the starting XI to Phil Foden, Raheem Sterling is yet to replicate the form that made him such a crucial asset to Guardiola.
The Catalan added, "On Saturday (vs Southampton), we struggled a bit, and that is why he (Sterling) didn’t get many balls, but he was always dangerous and ready to try to do it."
Though it remains to be seen how Pep Guardiola and his coaching staff try and get the ex-Liverpool star back firing, it was another timely reminder that playing Sterling up top is not a long-term solution to Manchester City's striking problems.
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