A colt by sire of the moment Fastnet Rock has fetched $1.35 million at the second session of the Magic Millions sale at the Gold Coast.

The yearling, our of Mister C mare Smart Company, was the first lot to break through the $1 million barrier following spirited bidding.

He was knocked down to Irish racing and breeding conglomerate Coolmore Stud which stands his sire.

Gai Waterhouse has been named as his trainer.

"We know how well the stallion is doing and the colt is a lovely individual," Coolmore's Tom Magnier said.

"I hope he is lucky, but he is by the right stallion. We are delighted to have him."

Waterhouse and bloodstock agent James Harron bought four yearlings by Fastnet Rock at Wednesday's opening session of the sale, including a filly for $500,000.

But the pair were in opposite corners on Thursday with Harron, representing prominent owner Dr Edmund Bateman, the underbidder on the $1.35 million colt.

Waterhouse was rapt the youngster would be heading to her stables, describing him as "poetry in motion" via a Magic Millions tweet.

"He just glides over the ground and the last horse I said was poetry in motion was Pierro - a champion," she said.

The third foal out of the former Waterhouse-trained Sliding Cube - who is from the family of champion sire Redoute's Choice and fledgling stallion Manhattan Rain - sold for $460,000 to former racing broadcaster David Raphael.

The yearling filly's half-sister Drifting Cube finished fifth on her debut at Ballarat on Thursday.