A fortnight after equalling her late father Tommy Smith’s Golden Slipper record, Gai Waterhouse will rely on three lightweight chances to surpass the champion trainer’s Doncaster feats when she shoots for an eighth win in the famed Randwick mile.

Group 1 winners Cosmic Endeavour and Diamond Drille will be joined by Saturday’s Neville Sellwood Stakes winner Pornichet in the $3 million feature on the opening day of The Championships, but Waterhouse remains fuming with the weight scale she blames for not running Prelude winner Excess Knowledge.

“They’re shockingly compressed,” said Waterhouse, who ruled out a start for Excess Knowledge despite being slated to carry just 50 kilograms.

“The ATC and Australian racing should be ashamed of the weight scale. In Victoria and South Australia you can get a much bigger spread sometimes yet we have a minimum of 50 [kilograms] and some of the top horses who have won majors on 55 kilograms.