Tegan Harrison survived a protest to win aboard Hi Son at Eagle Farm but she finished the day with a six-meeting careless riding suspension out of the race.
Harrison, a clear leader in the apprentice's premiership, was suspended for causing interference to Heza Jetsetter in the final 100m of the three-year-old handicap.
Stewards said Harrison had failed to stop riding and straighten Hi Son which caused Heza Jetsetter to be checked.
Ryan Wiggins, who rode Heza Jetsetter, lodged a protest against Hi Son but it was dismissed.
"Degree of carelessness high, degree of interference low," chairman of stewards Wade Birch told Harrison.
"You've been suspended five times for careless riding between May and September this year and we can't ignore your record."
Harrison can ride at Eagle Farm on Saturday before her suspension starts. She will resume riding on December 12.
Meanwhile, jockeys Dean Tanti and Luke Rolls were hospitalised after a three-horse fall near the 600m in the fifth race at the Gold Coast.
Tanti, who rode Romeo Lad, has a suspected broken leg and wrist while Rolls, the rider of As We Go By, has a suspected broken collarbone.
Daniel Griffin escaped unharmed despite his mount Elkalato being involved.