Manchester United 25-1 for title after being rocked by Brighton
City hit Huddersfield for six with Sergio Aguero grabbing a hat-trick
Albion, who had been 9-2 for victory, were 2-0 up before the half-hour mark thanks to goals from Glenn Murray and Shane Duffy, only for Romelu Lukaku to reduce the deficit on 34 minutes.
However, more shoddy defending from Eric Bailly saw the United defender concede a penalty which was converted by Pascal Gross on the stroke of half-time.
Paul Pogba also notched from the spot with seconds remaining but there was not enough time for United to launch a successful comeback in a poor display from the Red Devils.
It leaves Jose Mourinho's men in the almost unheard of position of being considered 25-1 fifth favourites for the title after only two matches of the new season.
They have also been pushed out to 11-10 by Betfred just to finish in the top four spots and BoyleSports promoted Mourinho to 4-1 favourite in the betting on the first Premier League manager to leave his current position.
Sergio Aguero scored a hat-trick, while there were also goals for David Silva and Gabriel Jesus as well as a Terence Kongolo own goal.
Aguero is 7-2 with bet365 for the Golden Boot and the same firm rate the champions 5-1 to break their own goalscoring record of 106 league goals in a season.
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