Pep Guardiola has said Abdukodir Khusanov "will learn" after the young defender's nightmare debut against Chelsea.
Khusanov gifted Chelsea a goal inside three minutes of his first City appearance following his £33.6m ($41.6m) move from Lens last week.
The 20-year-old Uzbekistan international was booked for a foul on Cole Palmer just a minute later and was eventually substituted early in the second half.
City recovered from their poor start to win 3-1 thanks to goals from Josko Gvardiol, Erling Haaland and Phil Foden to move back into the top four of the Premier League.
"Well, what I thought is not the best start, right?," Guardiola said.
"He will take a lesson. He's so young, he's come for many years. It's not the best start of course, but dealing with [Nicolas] Jackson, with Cole ]Palmer], with all these incredible players is not easy.
"He will learn. He's young, he will learn, I'm pretty sure. Take a lesson from that."
Khusanov was forced into an early debut at centre-back because of injuries to Rúben Dias and Nathan Aké. John Stones was only fit enough to be named on the bench.
Guardiola said needs Stones to be available for the crucial Champions League clash with Club Brugge on Wednesday.
Khusanov is not eligible to play in the Champions League and Dias and Ake remained sidelined, with City having to win to have a chance to progress from the league phase after a difficult campaign.
"I have to learn Russian or Uzbek to communicate with him [Khusanov]," Guardiola said.
"He doesn't speak fluently in English. In this kind of situation, there's nothing much to say. He knows he made a mistake.
"What can I say? Don't do a mistake? He doesn't want to do it, so we know that.
"I make a substitution mainly for the yellow card, not just for the mistake. I need John for Wednesday."