Ben Melham had to go the stewards' room before claiming an early double at Moonee Valley.
Winning the opening race aboard Strykum on Saturday, Melham was then second over the line in the SAJ Fruit Supply Handicap (2040m) aboard Shenzhou Steeds.
After being beaten a half head by Temps Voleur, Melham fired in a protest against Jye McNeil, alleging interference on home turn.
Melham claimed the interference had cost him "a length and momentum" before Shenzhou Steeds staged a late comeback to go down narrowly.
Stewards agreed, saying the interference caused Melham to stop riding for up to nine strides and they upheld the objection.
Shenzhou Steeds ($6) completed back-to-back city wins after being successful at Flemington on August 8.
The victory was trainer Mitchell Freedman's second metropolitan success with a gelding that has been in his stable since last October.
Freedman said the race hadn't panned out as expected with Count Of Limonade, wearing blinkers for the first time, getting out with a big break.
"I'm a relieved man," Freedman said.
"It's not the way I like to win races (on protest) but I'll take it."
Freedman revealed Shenzhou Steeds had received a small wound during the race which required his attention as the protest was being held.