Gundogan returned to the City starting XI for the first time since his recent injury on Saturday night, and he picked up directly where he left off - scoring the Blues' opening goal.
Capitalising on a mistake from Robert Sanchez in the Brighton goal, Bernardo Silva scooped the ball into the path of the German to hammer home his second of the season.
A successful return for Gundogan, but it was Phil Foden who stole the headlines with a Man of the Match display. Scoring two goals and setting up Riyad Mahrez for another, the 21-year-old was in full flow.
"He's amazing. He was already last season, he is this season. Exactly the type of player that we need to be successful," Gundogan told Manchester City when asked about Foden's performance.
"Today he was exceptional again. It doesn't matter if he plays up-front, if he plays on the left, it feels like with his mobility, with his movement, with his smell for the danger, he can help us in every single position."
Gundogan continued, "We are very pleased that we have him. Obviously we'll try to support him as much as possible, to continue the way he's playing."
The 31-year-old combined well with Phil Foden throughout the game, and will look to continue that relationship as Manchester City's hectic winter schedule starts to kick in.
Next up is West Ham at the London Stadium in the Carabao Cup fourth round, with the Blues looking to pick up the trophy for a record-breaking fifth consecutive time this season.
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