Manchester City s Gabriel Jesus, left, and Crystal Palace s Wilfried Zaha in discussion during the English Premier League soccer match between Manchester City and Crystal Palace at the Etihad Stadium, Manchester, England, Saturday Oct. 30, 2021. AP
City's hopes of recovering from Zaha's sixth-minute goal were hit when Aymeric Laporte was sent off in first-half stoppage time for bringing down Zaha when he was the last man.
Gabriel Jesus had a 60th-minute goal disallowed for a narrow offside against Phil Foden in the buildup.
Gallagher then added a second goal on the break in the 88th minute, consigning City to its first loss in the league since the opening round against Tottenham.
City dropped five points behind leader Chelsea.
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