Leading jockey Zac Purton has been left without a ride in the Group Three National Day Cup on October 1 after connections of Little Bridge decided to take him back in distance rather than up and will have to find a new jockey. After flirting with him as a Derby horse last season, the management of the Chief Executive's Cup runner-up will switch him back to the straight 1,000m course, over which he is unbeaten in four attempts, for the Sha Tin Sprint Trophy the same day. 'That leaves me without a ride in the 1,400m race and unfortunately I can't even ride Little Bridge in the 1,000m because I've made a firm commitment to Sacred Kingdom,' said Purton, who has won six of his 10 rides on Little Bridge. 'It's disappointing because they are both terrific horses and I would love to stay with both of them. I was hoping they wouldn't be crossing paths so soon.' Meanwhile, Hong Kong's Caulfield Cup-bound stayer Mighty High will be asked to carry a huge weight in his opening start at the Melbourne racing carnival on Saturday. Weights were released yesterday afternoon for the Caulfield meeting, where both John Moore's visitors, Mighty High and Silver Grecian, will appear for the first time and Darren Beadman will ride both. Mighty High will take on a plain open handicap over 1,700m as his pipe opener for the Caulfield Cup and will be well graded but pays for that with top weight of 135 pounds and conceding at least eight pounds to the next in the handicaps. Mighty High is listed by Australian bookmakers as a 60-1 outsider for the Caulfield Cup (2,400m) on October 15. Silver Grecian tackles the Group One HK$2.8 million Sir Rupert Clarke Stakes (1,400m) in which he has 120 pounds.