It has been less than smooth sailing getting Written By's preparation on track.

But trainer Grahame Begg is convinced he has a serious horse on his hands after the colt remained unbeaten in the Blue Diamond Prelude at Caulfield on Saturday.

Written By needed barrier education after failing to load in a recent Mornington jump-out which put Begg's plans to run in last week's Chairman's Stakes on hold.

After more remedial work the colt stepped out in the Group Three Blue Diamond colts and geldings Prelude (1100m) with Jordan Childs aboard and showed his quality.

Written By ($6), bred by Begg's father Neville Begg, raced three-wide near the speed and he had a half-length advantage over Plague Stone ($4.80) with 1-1/2 lengths to Native Solider ($9.50) third.

"We haven't really been able to train the horse properly," Begg said.

"Leading into both his starts he hasn't had a perfect preparation because of his barrier manners.

"But we've got on top of him now.

"He's got a great will to really find the line. He's just a dead-set racehorse."

Written By has firmed from $17 to $8 for the $1.5 million Group One Blue Diamond Stakes (1200m) in two weeks with last week's impressive Inglis Premier winner Kinky Boom and Prelude runner-up Plague Stone favourites at $7.

"We'll see how he pulls up and I'd say there would be every likelihood (he'll go to the Blue Diamond)," Begg said.

"Obviously we've got ambitions of going to Sydney. We'll just work it out.

"Obviously it is high on the agenda, don't get me wrong, but the horse will come first."