City missed out on the title to Arsenal last season and are expected to be the closest challengers again.
Maresca’s men remain ahead on goal difference but will be overtaken by the Gunners if they beat Liverpool on Sunday (kick-off 4:30 p.m. GMT).
City have conceded 10 goals in nine league matches this season, double what Mikel Arteta’s men have conceded.
Individual errors at the back are starting to pile up – Marc Guehi, who was sent off for this game, and Gianluigi Donnarumma were culprits at Villa Park and Matheus Nunes was the culprit against Brighton.
Maresca has been unequivocal about his number one, saying it is “Donnarumma plus 10” on the team sheet, but defensive weaknesses mean City have kept just one clean sheet in their last eight games in all competitions.
The result also meant City lost consecutive Premier League matches for the first time in 14 months.
“For what?” Maresca asked about individual errors. “Sometimes it happens.
“Unfortunately it happens to our players, but I think it’s part of the game, of football. It happens several times against us.
“We need to analyze what we can do better and try to move forward.”
Gn sports

