Top Queensland trainer Robert Heathcote believes rival Chris Waller has another feature race at his mercy, rating Moriarty as the horse to beat in Saturday's Brisbane Cup at Doomben.

Moriarty, who won the Group Two event in 2013 and finished runner-up 12 months ago, goes into this year's renewal after finishing second to Queensland Derby favourite Werther in the Eagle Farm Cup last weekend.

Heathcote has outsider Volkhere in the Brisbane Cup and expects him to improve on his last-start eighth in the Caloundra Cup three weeks ago.

But he doubts his charge can upstage Moriarty who Heathcote says is exceptionally well weighted.

"The conditions of the race are a quality and while my horse and a few others have 53 kilograms, Moriarty as the winner of $1.7 million in prize money does look very well placed with 59 kilograms," Heathcote said.

Moriarty is on the third line of betting at $5 with Victorian Lets Make Adeal the $3.30 favourite ahead of emerging Sydney stayer Sense Of Occasion at $4.80.

Volkhere is a $61 chance but Heathcote says he should be forgiven for his last-start failure at Caloundra which followed a good second to Pornichet in the Toowoomba Cup.

"The track was a bit firm for Volkhere at Caloundra," Heathcote said.

"He never really got a break in the lead. They kept attacking him and it was no wonder he stopped.

"Prior to that he was very honest and I would expect him to race better."

Meanwhile, Heathcote is resigned to fourth emergency Riva De Lago missing out on a start in the $2 million Stradbroke Handicap but says the horse is going well enough to feature during the winter carnival.

"Unless there is a miracle he won't get a run but he is going along nicely for later in the carnival," he said.