McKay said Puccini was a tired horse when he was being unsaddled and it took longer than usual for his heart rate to settle back.
"There were clear signs it had been an extremely tough race for him."
McKay said he wasn't entirely happy with Michael Walker's ride in pushing the horse forward through the first 400m to tackle the leader Shamus Award.
"I'm not keen on jockeys ignoring instructions and going out and making their own rules."
Stewards weren't impressed either and asked Walker and Shamus Award's rider Craig Williams why they didn't ride more patient races. Williams told stewards he simply couldn't restrain Shamus Award and Walker declared his saddle started to slip forward and letting Puccini run was his only option. "It meant he had a very hard run, much harder than it needed to be," said McKay.
Shamus Award dropped out and finished second last. Puccini led from the 1200m, but was beaten on the corner and faded to 12th, 12 lengths from the winner.
McKay said if the decision is made to go forward to the Derby, a second decision will be who rides the colt. "I've only ever made a commitment race by race for a jockey and Michael has not been engaged for the Derby.
"The only thing I'll say is that he's a little closer to keeping the ride than he was immediately after yesterday's race."
Walker told McKay that in his opinion Puccini was very unhappy in the rain-affected footing. "They were coming home in most of the race in 36 seconds from the 600m, which suggests the track was not too bad, but I listened to the stories from most of the jockeys in a couple of races and at least half were saying their horses were hopeless in the footing.
"The Derby is at Randwick of course and that's a different surface. My opinion is that if yesterday's races had been at Randwick the track would not have been anywhere near as bad."
One New Zealand camp that must have been pleased - delighted even - was the El Roca team after he finished a fabulous third in the A$1 million George Ryder Stakes.
Because of the weight structure, the George Ryder is an extremely difficult race for 3-year-olds to win. The Doncaster, El Roca's next mission, is much different - he drops to 50kg from Saturday's 56kg.
However, co-trainer Trent Busuttin is having second thoughts about the Doncaster and says he may switch El Roca - who has yet to win past 1200m - to the 1200m T J Smith instead. "I can't help but think he might be better suited over the sprints," Busuttin told Racenet in Sydney yesterday.
"He runs well in these races around the mile because he's such a good horse. A lot of trainers will tell you any top-class sprinter, genuine group one speedster, can run well in mile races."
The temptation of dropping back to the 1200m is offset by the "featherweight" El Roca will carry in the Doncaster. "He's only got 50kg in it and will probably start second or third favourite in the race so it's hard to bypass," he said.
And that's without mentioning the A$3 million on the line.
