A heart-stopping ride, a mystifying protest and the end of several spring carnival dreams - Saturday's Metropolitan at Randwick had it all.

Chris Waller emulated his earlier dominance in the Epsom Handicap producing the quinella in the Metropolitan when Junoob held off stablemate Opinion by a half length.

The race also provided jockey Blake Shinn with his second Group One of the day after claiming the Flight Stakes on First Seal.

It was a bold ride by Shinn who hit the front on Junoob around the home turn, banking on the horse's staying prowess to kick in at the finish.

It did, although horse and rider had to survive a protest from Tye Angland on Opinion alleging interference at the 600m.

It was an objection stewards didn't mull over too long and Junoob kept the race.

For Shinn, Epsom Handicap day was the ultimate sign of a career resurrected after a year spent sidelined due to a betting scandal and the loss of his close friend and supporter Guy Walter earlier this year.

"This is what it's all about, this is what we put in the hard yards for," Shinn said.

"It's not just about me, it's about the people who have supported me over the last couple of years since I've been back.

"You can't ask for a much better day, two Group Ones on a big feature day.

In a truly run 2400-metre staying test, Travolta set the tempo and strung the big field out.

Junoob stalked the speed in fourth and Shinn said the decision to hit the front early was one he momentarily regretted.

"I had a lapful of horse and I knew I had a big weight but I was travelling so well and I made a split-second decision, I thought the timing was right," Shinn said.

"I was starting to question my decision at the 300 (metres), thankfully the horse was a really good horse, he was trained to the minute and he dug deep when it counted."

The Metropolitan result was the icing on the cake for Waller, who along with claiming the Epsom also won support races with Brazen Beau and Moriarty.

His presence in the winner's stall has become a familiar feature but Waller takes nothing for granted.

"I never expect it," Waller said.

"But it's a good day.

Araldo did a grand job to finish hard for third while favourite Spillway and Makybe Diva's little sister La Amistad both look to be out of Caulfield Cup contention after finishing midfield.