The Kembla meeting on Thursday was abandoned after just three races, but there was time enough for Rubick to post his 25th first crop winner.
Trained by Gerald Ryan, three year-old colt Mr Mosaic made it a winning debut when he showed great speed and tenacity to post a short head win in the 1000 metre maiden.
Retained to race, Mr Mosaic is the fourth winner from Crazy Quality, a half-sister to the dam of Group II winner La Bella Dame, the dam of Group III winner Damselfly and stakes-winner Le Bonsir, the family also delivering Tasmanian stars Galvanized and Hot Dipped.
Crazy Quality has a two year-old colt to follow by Rubick and was covered again by him last spring
Coolmore based Rubick has the chance for a big payday on Saturday with his quality three year-old colt Yes Yes Yes running in the $14million The Everest for champion trainer Chris Waller.
A close runner-up last start in the Group I ATC Golden Rose, Yes Yes Yes has a light weight and will be ridden by in form jockey Glen Boss, fresh from winning the Group I ATC Epsom Handicap for the Waller stable on Kolding.