Thursday's second session of the Australian Magic Millions Gold Coast yearling sale boosted the auction's gross, but the average price is still tracking behind last year's.\nThe Thursday session produced a new sale-leader when trainer Gai Waterhouse went to about $644,000, to buy an Encosta de Lago filly out of former Australian champion Ha Ha.\nWaterhouse was bidding on behalf of Craig Thompson's Mount Hallowell Stud, a breeder and owner in Western Australian. Waterhouse trained the filly's dam to victories in the 2001 Golden Slipper and Flight Stakes. Ha Ha also was runner-up in Australia's 1000 Guineas that year.\nThompson said Waterhouse would train the Encosta de Lago filly and told reporters, "I came here specifically to buy this filly. Just have a look at her pedigree."\nAfter Thursday's session, the auction had sold 291 yearlings for about $35,119,160, up slightly more than 1 percent from last season's total at the same point. The average price was down 5 percent from last season's at about $120,684. The median was approximately $92,000, and buy-backs were running at 22 percent.\nThe auction's first section, consisting of four sessions, was to run through Jan. 9.