The Blues will host the Premier League leaders at Stamford Bridge in what is the biggest fixture of the 2017-18 domestic season so far.
Manchester City are sitting at the top of the Premier League table following a return of 16 points from their opening six games in the current campaign.
The Citizens have scored 21 times and have only conceded two goals to lay down a marker in the title race helped by a 5-0 win against Liverpool.
Chelsea lost 3-2 to Burnley in their opening fixture of the defence of their Premier League crown but are unbeaten in their last five games.
The defending champions beat Manchester City at The Etihad and Stamford Bridge last season en route to winning the Premier League crown.
Former Manchester City defender Mills believes the Premier League title holders will need to strike early if Antonio Conte’s side are to beat the early pacesetters.
“Man City still have defensive issues,” Mills told BBC Radio 5 Live.
“If you sit back against Man City, that’s when they’ll create chances. They just have to go for it. They might nick one early on.”
Chelsea have won the Premier League title in two of the past three seasons under different managers: Jose Mourinho and Conte.
The Blues haven’t won the Champions League crown since 2012.
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