Bookmakers have reacted swiftly to Shocking's win in the Makybe Diva Stakes winding him in to $8 to win back to back Melbourne Cups.After weights were released last week, Shocking was the $12 favourite despite receiving 57kg, six kilograms more than he carried to win last year.His come-from-behind performance to win over 1600 metres at Flemington on Saturday forced TAB Sportsbet to firm his price with some other bookmakers tightening him to $7.50 and $7.Trainer Mark Kavanagh is under no illusion

Bookmakers have reacted swiftly to Shocking's win in the Makybe Diva Stakes winding him in to $8 to win back to back Melbourne Cups.

After weights were released last week, Shocking was the $12 favourite despite receiving 57kg, six kilograms more than he carried to win last year.

His come-from-behind performance to win over 1600 metres at Flemington on Saturday forced TAB Sportsbet to firm his price with some other bookmakers tightening him to $7.50 and $7.

Trainer Mark Kavanagh is under no illusions about the task ahead of Shocking to become just the sixth horse to win Australia's most famous race more than once.

The others are Archer (1861-62), Peter Pan (1932 and 1934), Rain Lover (1968-69), Think Big (1974-75) and Makybe Diva (2003-04-05).

"It's a hard ask but he is unbeaten at Flemington," Kavanagh said.

"He's improved again this year and hopefully there's more to come.

"We have to protect his interests and make sure he doesn't get any (Cup) penalties so he'll more than likely follow the weight-for-age path.

"That doesn't entirely rule out the Caulfield Cup and there's a long way to go yet.

"Maybe you'll see him at Flemington right the way through as much as we can."

The Bart Cummings trio of So You Think ($14) Dariana and Faint Perfume, both $16, are next in Cup betting.

Cox Plate winner So You Think is set to run in Saturday's Dato Tan Chin Nam Stakes along with Faint Perfume.

After missing the autumn, So You Think made a great return to racing when he beat the Kavanagh-trained Whobegotyou in the Memsie Stakes on August 28 in which Faint Perfume was eighth after striking early interference.

Both So You Think and Faint Perfume are raced by raced by Dato Tan Chin Nam for whom the race is named.