The 35-year-old former England international, who has spent two seasons on loan with the Blues, is back for more at the Etihad Stadium
Scott Carson has, on the back of two seasons on loan at Manchester City, signed a one-year contract with the reigning Premier League champions.
The 35-year-old goalkeeper joins the Blues as a free agent after seeing his deal at Derby expire.
A veteran shot-stopper has taken in just one competitive appearance for City since first linking up with them in 2019 - with that solitary outing coming against Newcastle back in May - but he is a reliable back-up option behind Ederson and Zack Steffen.