Thomas Tuchel is facing his first real test as Chelsea manager following the Blues' 3-2 defeat to West Ham on Saturday.
Arthur Masuaku's freak 87th-minute winner condemned Chelsea to their first league defeat since September 25.
League leaders at the start of play, Chelsea finished the weekend in third and the bookies reacted by easing their odds on winning the title from 11/4 to 5/1.
"We give easy goals away," admitted Tuchel who said the trait had been a feature of their last three games.
Divock Origi's superb 94th-minute strike wrestled all three points from Molineux to rack up a fourth straight victory for Jurgen Klopp's side.
It saw Planet Sport Bet cut their odds on winning the title from 7/2 to 11/4.
Bernardo Silva scored twice for City whose odds on retaining their title were cut from 4/6 to 8/13 - City are six points better off at this stage of the season than they were last year.
There was also movement in the top-four betting, with West Ham's second 3-2 victory over one of the top three - they beat Liverpool by the same scoreline in November - seeing them cut to 10/3 to finish inside the Champions League berths.
At the bottom, there was little movement in the betting despite a Callum Wilson goal earning Newcastle their first win of the campaign.
The Magpies are 8/11 to suffer the drop, with Burnley, the team they beat, 10/11.
Norwich, who lost 3-0 at Tottenham, remain 2/9 favourites to go down.