Holders Arsenal are out of the FA Cup.
The Gunners lost 1-0 to Southampton in Saturday’s early kick-off.
Mikel Arteta made seven changes to the team that hammered Newcastle 3-0 on Monday, but they failed to create and convert chances.
Gabriel Magalhaes’ own goal proved to be decisive at Saint Marys.
Manchester City were given a huge scare by fourth-tier Cheltenham.
Pep Guardiola’s men went a goal down and with 10 minutes left, they fought back to score three times.
Goals from Phil Foden, Gabriel Jesus and Ferran Torres ensured City escaped a shock result in the late kick-off.