Champion jockey Glen Boss continued his outstanding form in big races when he picked up the late ride on Primitivo at the Gold Coast.

James McDonald was to ride Primitivo but when he failed to make the weight, Boss stepped up for the ride in the $1 million Magic Millions Trophy (2400m).

Trainer John Thompson said Boss produced an 11 out of 10 ride to get Primitivo ($8.50) home by 1-3/4 lengths to Black On Gold ($6) with a short neck to A Man To Match ($9) third.

The favourite The Candy Man ($3.20) was anchored by his 61kg and finished sixth.

Thompson said it was a nice position to be in to replace McDonald with Boss.

"When you can replace one champion with another you can't complain," Thompson said.

The Randwick-based trainer also deserves credit as Primitivo was going from 1600m to 2400m on Saturday.

"We were looking at the 1800m race today but when we had a look at the fields this looked easier and there was more money," Thompson said.

Primitivo was a $105,000 buy and lifted his earnings to nearly $800,000.

It has been a profitable season for Boss since switching from Singapore to Sydney in August.

Since then his big race wins have included The Everest on Yes Yes Yes as well as the Epsom Handicap and Golden Eagle on Kolding.

Boss said he had a lovely run throughout and was confident a long way from home.

"I thought I would get going early as this horse can really stay," he said.