Brett Prebble has become this season's 'King of Happy Valley' and can further cement his place on the throne with a full book of rides at tonight's meeting. Prebble has ridden 20 winners at the city track - almost double that of his nearest rival, apprentice Keith Yeung Ming-lun (11 wins) - and that statistic stands him in good stead. Prebble has been listed a $2.80 favourite in early betting, and should be able to topple in-form Douglas Whyte ($4), who stole the show at Sha Tin on Sunday with four winners. Interestingly, Yeung may be an outside chance at $17 as one of Prebble's few threats, but with Whyte and Yeung only boasting six rides each, both will need to score heavily with their main chances to be any hope. Kingston Temple and Glorious Giant have claims for Prebble in the first two races, while Master Rio looks a standout for the Australian in race three. From there, Unique Speed and Bolero will need some expert guidance from wide gates but, given the way Prebble has been steering them around the Valley of late, you wouldn't want to bet against that happening. Flying In is a major chance in the Cameron Handicap, while last-start winner Vanquish Delight will take a power of beating in the Police Cup. Double Luck can end the night on a high for Prebble, who has won the previous two Happy Valley Jockey Challenges and looks likely to chalk up a hat-trick.