Arrest firms to 3/1 to win the St Leger Stakes after Frankie Dettori made shock decision to ride Irish colt instead of ante-post favourite Gregory

Arrest has firmed to a 3/1 favourite to win the St Leger Stakes at Doncaster this Saturday following news that Frankie Dettori has decided to ride the Irish colt rather than ante-post favourite Gregory.

Most predicted that Dettori would be onboard Royal Ascot winner Gregory for his final ride in a British Classic.

However, given the recent rain that has fallen at Doncaster and with soft ground expected, the Italian has made the shock decision to jump in the saddle of his stablemate instead.

As a result of of the switch, Gregory has widened to third-favourite with Sky Bet, with the three-year-old garnering odds of 4/1 at the time of writing.

The second-favourite in the market is Aidan O'Brien's Continuous at 10/3, who won a Group 2 at York last time out. 

William Haggas' Desert Hero and the Gosden's Middle Earth round out the top five in the betting lines, with the pair of thoroughbreds priced at 5/1 and 7/1 respectively.

Sky Bet odds for St Leger Stakes:

Arrest 3/1

Continuous 10/3

Gregory 4/1

Desert Hero 5/1

Middle Earth 7/1

Chesspiece 10/1

Tower of London 11/1

Alexandroupolis 25/1