A big hike in weight is the main stumbling block between sprinter Most Important and a $500,000 bonus at Eagle Farm.

Most important won the first two legs of the Brisbane summer sprint crown, the Group Three George Moore Stakes and the Listed Lough Neagh Stakes.

The gelding contests the third leg, the Buffering Quality (1300m) on Saturday and a win will give him the $500,000 for winning all three legs.

Trainer Tony Gollan has no doubt the biggest problem facing his horse is his weight of 58 kilograms.

"He has gone up quickly in the ratings for winning two races. Before he won the George Moore he was an 83 rating horse and now he is a 102 rater," Gollan said.

"In other words he has gone up 19 points for winning two races. It make it hard for them."

But Gollan said Most Important was so tough and honest it would be a mistake to write him off.

"He has been racing since June and if anything he just keeps getting better. We gelded him before this campaign and he can still have a sweat before races but that is generally a good sign with him," Gollan said.

Most Important is raced by Linda Huddy who, along with her husband Graham, has had success in major races around Australia including Derby wins with Shoot Out and Preferment.

"But it is the first time she has had a horse running for such a big bonus," Gollan said.

He will also run Frespanol in the Buffering rather than the Bernborough Stakes over 1600m.

"He got a bit of a black eye at his last run and I thought I would freshen him up to get him ready for a 1400 metre race at the Sunshine Coast next month," Gollan said.

Meanwhile trainer Bruce Hill hopes Jeff Lloyd is a good judge after the jockey elected to ride Man of His Word in the Bernborough Stakes.

Lloyd has been riding another Bernborough runner, Coolring, who is trained by Bjorn Baker.

The runaway premiership leader will ride the other Baker runners at Eagle Farm but stuck with Man Of His Word on whom he won the Brisbane Handicap two weeks ago.