The only thing better would be if Ultra Bliss gave her family a quinella.

McDonald's Master Catch, with Mark Callaghan to drive, will be one of the top hopes in the $100,000 race, which has a barrier draw on Wednesday. One of the outsiders will be Ultra Bliss, which is trained by McDonald's father, Neil Thompson.

Master Catch won in a photo-finish in round one of the heats after a tough run outside the leader, while Ultra Bliss caused an upset on night two with a late sprint from behind the frontrunner.

McDonald hoped for a favourable draw on Wednesday but said Master Catch had shown his versatility from any position.

"It doesn't bother me where he draws but it would be good to see him not do all the work," McDonald said. "He's had some really tough runs. He always seems to lob in the chair or make the pace.

"He hasn't got high speed but he musters speed and he can lead if we ever want to. It would be good to let someone else do the work and we could come down the outside ... and maybe win."

McDonald hoped to get one over her father but said Ultra Bliss was a threat with the right run.

"It can go well and it was a good run the other night," she said. "If he could sit in behind something, he could outsprint them. Hopefully it's not my horse ... his can run second," she laughed.

Meanwhile, trainer Clayton Harmey's request to have Blake Hughes aboard one of his pair in the final has been denied.

Hughes steered Kanye Crusader and Western Heir to heat wins for Harmey but he does not have an A-grade licence, which is needed to drive in the group 1 final.

Harmey said Josh Osborn's A-grade licence had been approved and he would replace Hughes on one pacer. Jack Callaghan will drive the other.