Arsenic killed Australia’s greatest racing horse Phar Lap 74 years ago, a new scientific study reveals, The Daily Telegraph reports.

The story suggests a lethal dose of the poison was given to the Melbourne Cup champion about 35 hours before he collapsed and died in California on April 5, 1932.

Previous theories speculated the champion died of a stomach condition but many suspected foul play by US gangsters trying to avoid losses from Phar Lap’s continued success.

Phar Lap won 37 of 51 races in his four-year career including the 1930 Melbourne Cup