Written By has taken another important step on a path towards his major spring goal, winning a jump-out at Flemington in his first experience on the straight course.

Trainer Grahame Begg has aimed this year's Blue Diamond Stakes winner at Saturday week's Group One Coolmore Stud Stakes (1200m) for three-year-olds at Flemington.

Begg, who trains at a property on the Mornington Peninsula, was keen to give his stable star a look at the straight course before the Coolmore.

He took the opportunity to run him in the jump-out against a number of other quality three-year-old's on Friday morning.

"We knew this was probably going to be the day he was going to have to do it," Begg said.

"We've focused everything on this race and it's been a long-range plan. To get here in one piece (on Saturday week) will be great.

"Everything we've done he's come through with flying colours."

With his regular jockey Jordan Childs aboard, Written By narrowly won the 800m-heat with Voila, Long Leaf and Lean Mean Machine all close behind.

Golden Rose runner-up Zousain was also given a comfortable trial, finishing just behind the first four.

Trainer Chris Waller was pleased with all four of his three-year-olds in the heat - Zousain, Voila, Lean Mean Machine and Performer.

Waller said Zousain's hit-out was similar to that of the colt's sire Zoustar before he won the 2013 Coolmore.

Written By did everything Begg wanted to see from him.

"We weren't out to break the clock but he's just a natural racehorse and he just put himself there," he said.

"Whatever you do with him, he's very competitive.

"It's always advantageous to have a look at the straight and just make sure you're on the right leg and everything because they can get a bit lost, some horses.

"It was a good experience and good to give him a trip away from the farm."

Written By has won six of his seven starts, including his two at Caulfield this spring and Begg believes his style will suit straight racing.

"He's got a high cruising speed and an ability to kick off that," he said.