After years of statistical analysis, the breeder and former accountant broke through with a Group 1-winning horse.

That horse was Angel of Truth, the Gwenda Markwell-trained gelding winning the Australian Derby.

It was a dominant victory and the horse looked set for a Melbourne Cup bid.

Instead, the now four-year-old has struggled since the win, Angel of Truth turning in a number of disappointing performances.

After a tough spring, the gelding has failed to fire in four runs this autumn, the latest a seventh-place in the Tancred Stakes.

Saturday's Group 2 Chairman's Quality looms as a moment of truth, Williams desperate to see his horse return to the form he produced on this corresponding race meeting a year ago.

"At Randwick he always seems to lift," Williams said. "I expect him to show something very different at Randwick.

"He meets a lot of these horses on significantly better weight terms. He'd have to show something significantly better than previous races to warrant his level of ranking in the benchmark."

The past 12 months have been frustrating for Williams, Angel of Truth struggling to live up to the promise he showed as a three-year-old.

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Last year's Australian Oaks winner Verry Elleegant has kicked on since the performance, building towards an impressive victory in Tancred on Saturday.

While Williams acknowledges she is a product of the powerhouse Chris Waller stable, he is at a loss as to why Angel of Truth hasn't shown similar improvement.

"I haven't seen him in the last 12 months as good as he was 12 months ago. I don't know why, I'm not his trainer, we'll have to ask his trainer.

"I'll see how he goes, maybe he needs a change of environment. He's better than that, he's not showing it. Something's been wrong somewhere, I'm hoping that's now behind us and we'll see that in this race."

When Markwell and Williams mapped out Angel of Truth's autumn, the plan was to build towards next week's Sydney Cup.

Those plans are up in the air, with a good showing on Saturday required for the stable to even entertain a run in the 3200 metre race.

The 2600m Chairman's Quality is fairly open, favourite Carif paying $5 with the TAB fixed odds, while Angel of Truth sits at $13 and Williams is hoping his charge benefits from a favourable handicap.

"It really depends on how he performs this Saturday. If he doesn't perform, he's definitely not going to the Sydney Cup.

"It's a 2600m race, the quality has dropped from the Tancred, it's a different track. He's got no excuses really.

"If you look at the previous race, the Sky High Stakes, he was only beaten by three horses in front by less than a length and he had 58kg.

"I expect to see more on Saturday. It's the ideal distance and track. If we don't see improvement, I'll have to go back to the trainer and question what's going on."

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