Fresh from a Classic Irish Guineas double at the weekend, Johnny Murtagh apparently can't make his mind up over which horse to ride in the Investec Derby at Epsom.

A public gamble on Rip Van Winkle, which started on Friday, has continued to snowball.

As big as 12-1 with most firms before the weekend, the Galileo colt is now as short as 4-1 with Victor Chandler, with only stablemate Fame And Glory and John Oxx's 2,000 Guineas winner Sea The Stars ahead of him in the betting.

The weight of money suggests that Murtagh will stay loyal to the Aidan O'Brien-trained Rip Van Winkle - whom he rode to finish fourth in the Guineas - in preference to Derrinstown Stud Trial winner Fame And Glory, who has been pushed out to 7-2 by William Hill.

Murtagh insists that he has a "soft spot" for Rip Van Winkle, adding: "He is a great horse and from day one has always shown class."

But these comments - and the latest betting move - are in stark contrast to those made by O'Brien's stable jockey when casting doubts over Rip Van Winkle's stamina after the Guineas, in which the colt picked up well from an unpromising position.

"He has a great cruising speed, but I don't know if he'd stay a mile and a half," Murtagh told At The Races.

He added: "Newmarket is not the most straightforward track and I don't think he handled it that great."

The flat, wide-open spaces of Newmarket's Rowley Mile contrast markedly with Epsom's unforgiving undulations and camber.

O'Brien thinks Rip Van Winkle, who suffered an interrupted preparation before the mile Classic, will take it in his stride, however.

He said: "You can never be sure if they will handle the track at Epsom but he is very classy and I don't see any reason why he won't."

As the guessing games continue, William Hill are offering 100-1 that O'Brien saddles the first five home in the Derby and just 5-1 that he trains the first three. He has nine entries from the 20 that remain.