Sandbar was the final horse to make the Golden Slipper field but trainer Brad Widdup guarantees the colt is not there to make up the numbers.

The Hawkesbury trainer has experienced ups and downs with Sandbar since joining Damion Flower's Platinum Park training operation last May, and now the two-year-old has an opportunity to end his first preparation on a high.

Sandbar might have just squeezed into Saturday $3.5 million Group One feature at Rosehill, but once he drew barrier three on Tuesday his odds improved significantly.

After opening at $21 before the draw, he shortened to $17 and then $11.

Widdup is pleased with the gate and will be rapt if forecast rain eventuates given Sandbar has won on soft ground.

Initially he had been reluctant to back Sandbar up after his dogged run in the Pago Pago Stakes last Saturday, when he pushed Golden Slipper second-elect Written By to the line before being shaded by a half-neck.

"The horse has made it an easy decision. He's pulled up excellent," Widdup said.

"Maybe it's not ideal backing up in a week after a hard run but he's thrown some good signs off that he's come through really well.

"I don't want to have a horse in the Slipper just for the sake of it. I want one that's a hundred per cent going in to the race."

Widdup always thought Sandbar was headed for a major two-year-old race, but he assumed it would be at the Gold Coast Magic Millions carnival in January.

"I was trying to get him right for the Magic Millions and we had a little mishap in the pool," he said.

"I was disappointed but I'll give him one thing, he's been in work all that time. He's rebounded and his races have been fantastic."

Sandbar became Widdup's first stakes winner when he claimed the Listed Lonhro Plate, a victory that justified Widdup's decision to join Flower, one of Australia's leading owners.

"Damion just rang me out of the blue. I didn't know him well at all," Widdup said.

"I took a little bit of persuading because I had a job. I was very firmly entrenched at Godolphin.

"I guess there had to be a point where I did something else. Damion just came along at the right time."