Confirming a liking for Flemington, Decircles landed his first feature-race win on Thursday.
After running third in the Standish Handicap 12 months ago, Decircles tracked the speed set by Lord Of The Sky before taking out the 2015 edition.
Ridden by Stephen Baster, Decircles, backed from $12 to $9, scored a three-quarter length win over Lord Of The Sky ($4) with the favourite Reparations ($3.80) 1-1/4 lengths away third.
It was the third win in the Standish for trainer Danny O'Brien and second for the O'Brien-Baster combination, coming 11 years after Blessum's success.
Decircles has done most of his racing at Flemington where he is trained and O'Brien said he had been going better than his recent form had indicated.
"He ran second in a Sires' as a two-year-old, he's had a wind operation, but at this time of the year he keeps putting himself in the frame," O'Brien said.
"I said to Stephen Baster I want to see you on that inside rail.
"Luckily Noel (Callow) took up the running on Lord Of The Sky and gave him a bunny to follow and inside the furlong it was only going to be him or Decircles.
O'Brien said Decircles would now head to the Chester Manifold Stakes Stakes (1400m) at Flemington on January 17.
Baster said a decision to use a tongue tie again combined with a drop in distance had been beneficial to the gelding.
"He's one of those horses that likes it free rolling and comfortable and it turned out perfectly today," Baster said.
Trainer Robbie Laing said he was likely to press ahead with plans to run in the Chester Manifold Stakes with Lord Of The Sky.
"I have mixed emotions," Laing said.
"He went great but he got beat. But he showed he's close to winning a good one again."