The decision to remain in Melbourne has been rewarded for Beau Mertens, who has moved to within two wins of the lead in the metropolitan jockeys' premiership after a winning treble at Flemington.

Mertens could have ridden in a feature race in Adelaide on Saturday but the apprentice elected to take a full book of rides at Flemington, winning aboard Divine Quality, Hot Ruby and Stormsabrewing.

It took the apprentice's season tally in Melbourne to 55, closing the gap to two behind reigning premier jockey Craig Williams.

Williams rode in Adelaide on Saturday at the meeting, which featured two Group One races, while Mertens, who is apprenticed to trainer Mick Kent, said he had the opportunity to ride Bassett in the Group Three DC McKay Stakes.

Bassett finished sixth in Saturday's race at Morphettville.

"My master and I spoke with my manager and we thought it was best to stay in Melbourne," 19-year-old Mertens said.

"And it's paid off."

Mertens brought up his treble when Stormsabrewing got home narrowly in the final race of the day.

"It's getting close," Mertens said of the premiership race.

"I've just got to keep the momentum up and keep ticking over and hopefully things go my way.

"I knew I had the rides today. It was just whether the horses and I performed on the day. And it happened."

The season runs until the end of July.