Golden Slipper-winning jockey Ben Melham has lost his battle to ride She Will Reign in The Everest.
Melham and She Will Reign combined to win the world's richest two-year-old race in March and connection have earmarked a crack at the $10 million Everest on October 14.
Melham had already conceded he could not make the 50kg to ride She Will Reign at weight-for-age when she resumes in the Group I Moir Stakes (1000m) on September 29 but told RSN927 on Wednesday that he would not be able to do 51kg in The Everest.
Melham said he contacted She Will Reign's trainer Gary Portelli and syndicator Scott Darby to advise them of his decision on Sunday.
"I'd been thinking quite hard about it and been training for six or seven weeks and dieting and stuff like that and I just felt 51(kg) was just beyond me," Melham said.
"(A) 52(kg weight) wouldn't have been a problem but I just decided it was better to let them know now while they have got plenty of time.
"They have limited options with that kind of weight and I didn't want to get close to the date and work out that it was going to be too light for me.
"At the end of the day, you can only do what the body will allow you. I was better keeping in good shape mentally and physically."
Melham's decision gives Portelli more than three weeks to find a jockey for She Will Reign for The Everest with few of Australia's top jockeys able to ride at 51kg.
Magic Millions 2YO Classic winner Houtzen will also require a lightweight rider to pilot her at 51kg in The Everest where she will represent Queensland breeder Aquis Stud.
Craig Williams rode Houtzen in her third in the McEwen Stakes at Moonee Valley on September 9 but he will miss the Moir Stakes meeting through a suspension he incurred for his part in Damian Lane's fall at Flemington last Saturday.