It isn't often that picking up the ride on a two-time Horse of the Year could be called a thankless task but that's what in-form jockey Zac Purton may have ahead of him in the Group Two Oriental Watch Sha Tin Trophy (1,600m) today on Ambitious Dragon. Purton is the third rider for the Tony Millard-trained six-year-old in as many starts, after Douglas Whyte's sacking and Umberto Rispoli's cameo part for the Champions & Chater Cup. Rispoli is on his way back next month, and there is no telling

It isn't often that picking up the ride on a two-time Horse of the Year could be called a thankless task but that's what in-form jockey Zac Purton may have ahead of him in the Group Two Oriental Watch Sha Tin Trophy (1,600m) today on Ambitious Dragon.

Purton is the third rider for the Tony Millard-trained six-year-old in as many starts, after Douglas Whyte's sacking and Umberto Rispoli's cameo part for the Champions & Chater Cup.

Rispoli is on his way back next month, and there is no telling whether Purton will still have the mount, so he will be out to make the best of things - and a case for his continued engagement - in the Sha Tin feature this afternoon on Ambitious Dragon.

No-one is riding better than Purton, his confidence is high and all of that is going to be vital from gate one on a get-back horse in a race which promises a muddling tempo. He is on the best horse, a horse with a great record fresh and one fully capable of winning this even with top weight, but his greatest enemies will be the state of the horse's fitness and even moreso the play-out of the race itself.

The best thing that could happen to the Sha Tin Trophy is that one or both of the on-pace stayers, Mighty High and Liberator, can show enough pace from the jump to take up the running and roll them along at a reasonable tempo, but neither has shown all that much speed at 1,600m previously.

Failing that, the horses most capable of leading look to be Helene Spirit, Admiration, and even Familists has pace if ridden to use it, but they would all be reluctant leaders.

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