Robert Smerdon is gambling on the weight relief that comes with a rise in class to get Spreadeagled back into winning form at Flemington.

Spreadeagled heads to the Flemington Event Staff Handicap on Saturday, a 1600m benchmark 90 race.

At his last start Spreadeagled finished just behind the placegetters in a benchmark 84 race at a Moonee Valley midweek meeting on July 13.

For added insurance the trainer has called on the services of claiming apprentice Beau Mertens to partner the rising the five-year-old, replacing senior jockey Dwayne Dunn.

"We've gone the double whammy," Smerdon said.

"He drops a lot in weight and will get on to better footing which I think he'll be more effective on.

"He's OK on soft ground but I think Moonee Valley found him out, but notwithstanding that he was a little plain in the latter stages."

Spreadeagled will carry 53.5kg after Mertens' claim.

New Zealand bred and raced by Peter Mitchell of Cox Plate winner Bonecrusher fame, Spreadeagled has won five of his 10 starts for Smerdon.

Spreadeagled scored at his first start for Smerdon last December and has raced every month since, except for a short break in April.

Smerdon said Saturday's run would determine whether he pushed ahead with Spreadeagled or turned the gelding out for a break.

"He's climbed the ladder now but he's still got to go and take those next steps," Smerdon said.

"Can he take another one, that's the thing.

"This run will assess where we are and then we'll work out where to go from there."

Spreadeagled has met with early betting support and is the $5 second favourite having firmed from $7 while top pick Jerilderie Letter has also had support from $5 to $3.40.

Smerdon only has a light muster on Saturday and saddles $61 chance Cooldini in Spreadeagled's race along with $3.60 favourite Ability in the VRC Recognition Handicap.

Ability is owned by the estate of Phil Sly and Smerdon said there had been talk of a sale, but while there were offers, nothing came of them.

"He's been in training for quite a while," Smerdon said.

"I think he's going really well and we're taking him to the races with some sort of optimism."