Despite starting and scoring against Burton Albion, Kevin De Bruyne wasn't happy with Pep Guardiola.
Kevin De Bruyne started in midfield against Burton in the League Cup semi-final first-leg, and he gave his side an early lead.
He headed home in the fifth minute which began City's rout of Burton.
City added another eight goals though De Bruyne only lasted 58 minutes.
He was replaced in the second-half by Phil Foden - who also got on the score-sheet, and after being subbed, the Belgium international reacted angrily.
He went straight down the tunnel as he had hoped to get a few more minutes under his belt to improve his match fitness, according to The Times.
City were five-nil up against their League One opposition as De Bruyne departed the field.
Whilst Pep Guardiola wanted to preserve his influential midfielder, it appears De Bruyne wanted to continue playing on Wednesday night.
The 27-year-old has only managed six appearances in the league so far this campaign following two knee injuries in the space of a few months.
He was an extremely important player under Guardiola last season, and the Spaniard will be hoping he has his main man fit and raring to go ahead of the second half of the season.
The League Cup defending champions eventually slotted four more goals after De Bruyne left the field.
City take a nine (!!) goal lead into the second leg ahead of facing either Spurs or Chelsea in the final.
Anyway, City are back in action on Monday night as they resume their Premier League campaign versus Wolverhampton Wanderers.
The holders will be seeking to build on from their victory against Liverpool by securing maximum points.