There was a hole in the canvas, the frame was barely holding together and years of grime coated its surface, the only identification being a simple inscription, "Postboy 1875", in the bottom corner.

Undeterred, the passionate horse lover had just the place in mind for it among her extensive collection of all things equine.

"I loved it even though it was grotty," the former Warrnambool Racing Club chairwoman recalled.

"I bought it because I loved it but I had no idea what it was."

Beneath the shabby facade, she discovered, was a piece of Warrnambool's rich racing history.

But more than that, lurked a mystery that lingers even now, nearly 150 years on as the city prepares to celebrate this week's legendary May Racing Carnival.

Postboy was just the fourth horse to write his name in Warrnambool racing history as a Grand Annual Steeplechase winner.

Even more significant was that the legendary Irish hoop, Tommy Corrigan, was in the saddle when the pair saluted the judge first in the 13-horse field to claim the 1875 Handicap Steeplechase, renamed the Grand Annual in 1895.

Initially, Mrs Lucas was unaware that the Postboy of her painting, and the 1875 Grand Annual winner were one and the same.

Research uncovered another Post Boy of note, a dark chestnut mount who had made his name in the American north-south match racing era of the early 1800s.

The date seemed to discount the American contender.

It wasn't until about a year later that Mrs Lucas stumbled on the proof that her Postboy was all she'd imagined - a true champion of the turf.

Browsing one night through her copy of George Stevens' Western District racing history book, Silk and Saddles, she couldn't believe her eyes when the page fell open at a very familiar image.

Although black and white, there was no disputing the photo and her colour painting of Postboy were the same.

Well, almost.

"I just about levitated off the couch," Mrs Lucas recalled.

The caption confirmed it.

"Postboy: A son of the great Panic and winner of the 1875 Grand Annual," it read.

"The great Tom Corrigan rode Postboy in his first of four Grand Annual winners."

However, it was only on closer inspection that she noticed a number of minor differences between the two images.

The reins were crossed differently and the timber panels on what appears to be a feed bin are laid in different directions.

Mrs Lucas was intrigued.

Why the differences, where was the painting from the book now, what was the provenance of her own copy and who was the artist responsible?

She backtracked in an attempt to find answers.

Warrnambool photographer Peter Clayfield had purchased the painting at a district auction several months before Mrs Lucas spied it among the bric-a-brac and collectibles at his Fletcher Jones market stall.

"I just bought it as an interesting piece. I like older antique photos and images and I knew Marg was heavily involved in racing," Mr Clayfield said.

"It was quite stunning, although it was fairly shabby with a bit of a hole in it."

Mrs Lucas consulted prominent local artist Gareth Colliton for further clues.

Describing its style as "slightly nave or stylized", the artist ventured that it was of a similar ilk to local 19th century painter Daniel Clarke's work.

The former Warrnambool Art Gallery curator cited two almost identical paintings by Clarke of the Hopkins River.

"It wouldn't be surprising if there was more than one version of this painting. It wasn't uncommon in the day for someone to request the artist paint another copy of a popular painting," he said.

Question marks aside, Mrs Lucas decided her Postboy deserved a little more love and attention than it had been shown for some time.

"It had had a very sad life," she said.

"It needed restoring.

"It was badly damaged and in need of cleaning and stabilizing."

The painting was packed off to Melbourne to a recommended restorer while Mrs Lucas nervously awaited its return.

It was expected to take about six weeks, but then the pandemic struck.

It was closer to a year before a refreshed Postboy was returned safely back to its relieved owner.

"I was absolutely thrilled with the result," Mrs Lucas said.

"It just comes to life on the canvas."

Postboy now takes pride of place on her dining room wall, but the proud owner is still keen to know the full story behind her latest acquisition.

Bruce Lowenthal, the district auctioneer who sold Postboy to Peter Clayfield several ago, remembers the painting as being part of a deceased house estate.

It's believed the owner was a former woodwork teacher at the old Warrnambool North Technical school which merged with Warrnambool High School in 1993 to form Warrnambool College.

Whether the teacher had a personal connection to the painting is unknown, but Mr Lowenthal does recall it was part of an extensive collection.

"These people were serious collectors with a very diverse collection of things," he said.

"But there didn't seem to be much other racing material, so it's more likely that they purchased the painting because they liked it, rather than because they had a racing connection."

What's in no doubt is that Postboy was a truly local champion.

Sired by the esteemed Panic, he was bred by John McGuinness and trained by one of the district's former leading riders, Hugh Gallagher.

According to author Mark McNamara, in his book "The 'Bool. The History of Racing in Warrnambool from 1848", Postboy was one of the few horses to have won at the old Jetty Flat course, in 1873, and the new course in 1875.

"Postboy was a Warrnambool and district horse through and through," he wrote.

Warrnambool's Winter Steeplechase meeting was founded as a one-day meet in 1872.

By 1875, in the year of Postboy's grand annual triumph, it had grown to two days with four races on each day.

Postboy had already given notice of things to come, dead-heating for second place in the Handicap Hurdle Race on the first day's racing.

But it was on day two that Postboy delivered for popular handlebar-moustachioed Irish jockey Tommy Corrigan, winning what would be the first of Corrigan's eventual four Grand Annuals.

His other triumphs followed in 1876 on Aeneas, Left Bower in 1879 and on Aslanbegoff in 1882.

Corrigan had already ridden in the Melbourne Cup in 1872 and went on to become one of the leading all-time cross-country riders.

He later cited Postboy as "the first real good one" he won a race on over fences.

Born in Ireland, Corrigan migrated with his parents to Australia at the age of 13 and began working for his father on a dairy farm near Woodford.

The respected jockey enjoyed his first home-town success as a 14-year-old, taking home his prize of a saddle after winning a hack event at the Woodford publicans' picnic races.

By the time of his death aged 40 in a jumps accident in the 1894 Grand National Steeplechase, Corrigan had notched up 238 wins, 135 seconds and 95 third-placings from 788 starts and was unplaced just 319 times.

A devoted family man and a good Catholic, Corrigan was said to have gone to confession before each of his races.

His funeral cortege was reported as the largest seen in Melbourne.

Flags were flown at half-mast around the city; traffic was stopped for two hours as thousands of mourners lined the route and shops closed for the day.

The diminutive Irishman was memorialized by noted bush poet, Banjo Paterson, in his poem "Tommy Corrigan".