The reigning Fremantle Cup champion is set to line up in Friday night's Governors Cup (2130m), where a golden ticket to this year's edition of the Fremantle Cup is up for grabs.

Justin Prentice said he hoped Mighty Ronaldo, who finished sixth in the $50,000 event, had an off night.

"With the run he had you would think he would be the horse to beat," Prentice told The Trots WA.

"He didn't seem himself on the night and sweated up quite badly, which is not like him.

"He seems to have pulled up well and we all know he's better than that."

Friday's Governors Cup looms as a crucial race in Mighty Ronaldo's campaign.

Not only is the six-year-old battling with stablemate Tricky Miki to fill the JP Pacing slot in the TAB touch Nullarbor (2536m), he will also be out to cement his spot in the top 12 on the Fremantle Cup rankings, where he currently sits at number 10.

Tricky Miki, off the back of his Golden Nugget and Lord Mayors Cup wins over summer, sits at number six on the rankings.

Prentice said there was very little separating Mighty Ronaldo and Tricky Miki in the race to secure the coveted Nullarbor slot.

"It's probably 50/50 between them right now," he said.

"We will see how they go on Friday and then meet with everyone that's part of the slot next Monday.

"Tricky Miki has handled every challenge I've thrown at him so far and I think the distance and tempo of those races will suit him."

Meanwhile, Prentice is confident Never Ending's game fifth placing in the Bunbury Cup will hold him in good stead for his Nullarbor assault.

Never Ending worked his way to the breeze outside Swingband and was eventually beaten 4.7m.

Prentice said he was happy enough with how Never Ending, who was driven by Gary Hall Jnr, handled his first Free-For-All event.

"I thought he went well because the plan wasn't to drive him like that," he said.

"Junior just felt the speed they were going, together with being the favourite, that it was hard to drive him cold.

"As soon as he went they clapped the tempo on.

"Junior was surprised how small the margin was, considering he couldn't drive him the last 400 metres because he was hanging so bad.

"He should benefit a lot from that run."