Bred by the estate of the late L. A. Alexander, Think Big was purchased by Australian trainer Bart Cummings for Malaysian businessman, Dato Tan Chin Nam for $10,000 at the Trentham yearling sales in New Zealand.
[2] He was conditioned for racing by Cummings, who maintained a share in the horse, Think Big started eight times at age two, earning just one win.
The popular Bart Cummings trained mare Leilani was the favourite for the 1974 Melbourne Cup but she was run down in the last fifty metres by her stablemate Think Big under jockey Harry White.
But at his favourite course and distance, again under jockey Harry White, he fought off a challenge from stablemate Holiday Waggon to record his second win.
A gelding, after his racing career was over Think Big lived out his days at jockey Harry White's 200-hectare farm in Gisborne near Victoria, Australia where he died, on 23 February 1995, and is buried.