Auvray will target the resurrected $500,000 St Leger on Everest Day after winning the Colin Stephen Quality at Rosehill yesterday.
The Irish import survived a protest from second-placed Admiral Jello to follow up his win in the Randwick Mayor's Cup last month.
The seven-year-old gelding pipped Admiral Jello by a short-head in a grandstand finish to the Group Three staying test over 2400m.
Pacemaker Broadside, the favourite, finished a half-neck back in third.
Corey Brown argued Admiral Jello had been impeded when the Glyn Schofield-ridden Auvray shifted in at the 200m, costing the Kris Lees-trained gelding victory.
"It was enough to stop the momentum of my horse at a vital stage, I've no doubt I would have got over the top of them," Brown said.
However, stewards described the contact as minimal and ruled it did not have a bearing on the result.
Will Freedman, standing in for father Richard Freedman due to the trainer's television commitments at Caulfield, said Auvray's superior stamina was pivotal after he backed up from a runner-up placing in the Newcastle Gold Cup (2300m).
Freedman said the St Leger, a 2600m staying test was now the likely goal at Randwick on October 14.
"That was a pretty tough run so I think that's the likely result."
The Australian Turf Club revived the race for the undercard of the inaugural $10 million Everest.
The St Leger, which was first run in 1841, was previously held in the autumn and the last edition was won by Sky Heights in 2001.
Meanwhile, the temptation to run Washington Heights in the Epsom Handicap is strong after his qualifying win in the Shannon Stakes at Rosehill but connections will let the dust settle on his group 2 win.
Trainer Gerald Ryan had to convince his owners to run over the 1500 metres of yesterday's Shannon, but is reluctant to back him up seven days after he proved that distance was well within his range.
Washington Heights came from the tail of the field to post a half-length victory over Mighty Lucky.
"I'm sure he would get 1600 metres on that performance even though I had to talk everyone into running him over 1500," Ryan said.
"But I think we have found the key to him which is to space his runs three or four weeks apart."