Peter Snowden admits he is going into the Cox Plate with Long John in a different mindset than two years ago when he saddled up another three-year-old, Helmet.

Long John goes to Saturday's race off a Caulfield Guineas victory as Helmet did, but carries less expectation.

Sent out the favourite, Helmet failed to fire in the weight-for-age showpiece at Moonee Valley and finished midfield.

Armed with the knowledge gained from 2011, Snowden pressed ahead to the $3 million race with Long John, believing the gelding has something in the tank after his fighting Guineas victory.

"For me there was a lot of pressure on Helmet. He was expected to win and it didn't come off," Snowden said.

"It's an even race this time. I'm going in with an open mind and just knowing the horse is well and racing well."

While Long John is not favourite, he has been well supported with bookmakers around the country including being the best backed in the past 24 hours with TAB fixed odds.

It's A Dundeel remains the solid favourite at $4 while Fiorente has been a drifter from $4.60 to $6 since Tuesday's barrier draw.

Snowden said the best part about Long John's Guineas success was that he didn't have a "gut buster" like Helmet who ran a race record.

"He's come on well so there was no hesitation in my mind to give him his chance," he said.

"He's been very strong late and I feel if I didn't give the horse the opportunity I would be robbing him of that possibility (of winning a Cox Plate)."

Snowden is the head trainer in Australia for Sheikh Mohammed's Darley operation and each year horses are selected to join the Godolphin arm of the sheikh's racing business in Europe.

Helmet and Sepoy headed over a couple of years ago, Group One winner Mental left after last year's spring and Long John is a possibility this time around.

Kerrin McEvoy has had to get down to 49.5kg to ride Long John and is striving to join an elite list of jockeys to have won all four `majors' in Australian racing.

Snowden said he expected McEvoy to be positive to use the weight advantage.

"These are real proven 2000-metre horses and they'll be very strong late so we need to take advantage of our weight situation and put him in the first three or four at least and give himself a chance when they do start to quicken up," he said.

"He's shown before he can keep finding something when he's challenged."