The gelding charged home after jockey Glen Boss found clear air down the straight to pass runner-up Dreamforce and hold off a fast-finishing Avilius.

The run continued an impressive campaign for the five-year-old, the horse having won the Group 3 Liverpool City Cup before finishing second in the Group 2 Ajax Stakes.

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With three races under his belt and a guaranteed start in the Doncaster, Parker now has his sights sets on one of the biggest races in the country.

"It's absolutely terrific," Parker told Sky Racing. "It was just a gun ride from Bossy today. He took all the short cuts, which he's been able to do on him.

"I was still sitting borderline (for the Doncaster), I had me 20th to 21st, then whatever wins the prelude jumps me. I was thinking 'gee I hope we get in'. I needed a few to fall away.

"That was always the aim. Randwick on the big track, you go into it a live chance."

Think It Over has continued to improve with each campaign. Saturday's victory saw him beat a number of highly-fancied rivals, including Kolding and Avilius.

After winning at level weights, Parker's charge will meet them on more favourable handicap terms in the Doncaster and the trainer is optimistic about his chances.

"The last time we met those guys, they beat him seven lengths. He's improved a lot, he's very professional now. He knows what he's here for, he turns up on race day, it's all business.

"Coming into today, I thought 'I just need him to run well, if he's a couple of lengths from them I'll be thrilled, taking 7kg off him back to the Doncaster'. To win it is sensational."

Boss first rode Think It Over last year and said the improvement in the gelding has been significant.

"I really have a soft spot for this horse," Boss said. "I got on him over 12 months ago and I said to Kerry 'just keep sticking with this horse and go about your business. There's something about this horse and I think he's going to be a really good horse for you.

"This preparation he's has come back a lot better horse, more in his mind. He goes to the barriers now very calm, he's in control of everything he's doing now."