[2] He moved to South Australia and played for the Booleroo Centre Football club in the Flinders Ranges.
When war broke out Sadlier became the first player from the club to enlist, signing up on 20 August 1914.
He first saw action at Gallipoli with the 3rd Light Horse, then later in the trenches of France with the 5th Battalion finishing the war as a 2nd Lieutenant.
Returning to Australia on 12 March 1918, he didn't continue playing football after the war and moved to Trundle in New South Wales.
His brother, Clifford Sadlier, also enlisted and won the Victoria Cross at the battle of Villers-Bretonneux.