Although Tycoon Bec is by Written Tycoon from the moment Matt Cumani set eyes on her as a yearling he felt she was going to be a stayer.

Written Tycoon is one of Australia's great sires of speed horses but Cumani felt that Tycoon Bec didn't fit the mould of his horses.

"When I bought her I thought she wasn't your typical Written Tycoon. She was a more lightly framed, lightly boned horse with flat pasterns who had a lovely walking style," Cumani said.

"Everything about her suggested she would be a stayer and she was out of Singspiel mare so that's more of a European influence."

At Flemington on Saturday, Tycoon Bec will attempt to keep her undefeated record intact when she tackles the 1800m Benchmark 80 and prove Cumani correct.

Already she has won her debut at Kyneton over 1450m in a maiden and then her last start over 1523m at The Valley in a Class One, each time leading throughout.

"Her Valley win didn't impress the commentator Terry Bailey who said she was unimpressive but I thought she was. She was clearly quite green and inexperienced," he said.

"2000 metres horses like her often reach a flat spot around the last 200 metres of 1400 metres to 1600 metres races as they don't have an immediate switch up in gear. After the line she was really strong again."

The four-year-old mare is raced by a group headed by Perth businessman Peter Diamond, celebrity couple Chris and Bec Judd and actor Gary Sweet.

He concedes Tycoon Bec's inexperience could be a weakness on Saturday but he feels the rise in distance rise can mitigate the step up in class.

"I think the further she'll go the more she'll get to her top gear," he said.

Cumani said Tycoon Bec didn't have to lead over a longer trip as she had done in her two wins as she had done that to take trouble out of the equation.

Cumani said if Tycoon Bec ran well he would chase black type with her in the Birthday Cup at Morphettville on February 6.