His win “defied belief” in their first clash but Zac Purton has heaped the pressure on the Paul O’Sullivan-trained Duke Wai to do it again in his second showdown against speed-machine Lucky More.

Purton looked all but certain to win on Danny Shum Chap-shing’s colt last month before Karis Teetan came from the clouds on Duke Wai to win, with both horses going on to win in their own right subsequently.

They clash again in the Class Three Long Valley Handicap (1,000m) at Sha Tin on Saturday where Purton will look to settle the score with Teetan.

“He beat me fair and square the first time, there was no fluke about his win,” he said.

Duke Wai races up the centre of the track to beat Lucky More last month.

“He gave me a big start, it defied belief really to come from where he did to win, so if he gets out of the gates a little better and is within striking distance, he is the one to beat again.”

Lucky More looks a progressive type, coming off an arrogant four-and-a-quarter length win last start, where Purton sat near-motionless on the three-year-old.

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While that victory came in Class Four, Purton believes there should be no issues stepping up in grade for the first time.

“I don’t think it is a concern, he has shown he has the ability to handle Class Three, it’s just going to depend on what type of race it is and what type of run we get,” he said.

“I wouldn’t say he has improved a lot but he has held his form.”

Purton again lamented the fact he was engaged in a speed battle with rival jockey Joao Moreira during Lucky More’s debut run, which he believes cost him the race.

While Moreira rode Flying Genius on the first occasion, he will ride Chris So Wai-yin’s Classic Unicorn this time around.

The four-year-old showed plenty of promise during his first two starts, going undefeated over the 1,000m trip last season before being well beaten as a $1.4 favourite in his only start this term.

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At his best, Classic Unicorn has blinding speed that could see Moreira again match motors with Purton, something the Australian is hoping does not happen.

“[Lucky More] took a lot of improvement out of his first-up run, he really got driven mad in that race,” he said.

Trainer Danny Shum with jockey Zac Purton after the win of Lucky More.

“I suppose it cleaned his wind out nice and proper because the next run he was able to go through his gears a little bit more comfortably.

“I’m not sure how they want to ride [Classic Unicorn], we will have to work that out as we go. We know who’s on it, we know who drove me mad first-up.”

With no shortage of speed in the race, Karis Teetan is set to be the beneficiary on Duke Wai.

While only lightly raced, the four-year-old looks to have improved considerably this season, putting in a career-best run up in grade earlier this month.

While he looks likely to enjoy running over extra ground in time, O’Sullivan said he was happy to keep running his galloper over the straight 1,000m trip for as long as he was winning.