Jack O'Reilly was an Australian rugby league player and coach for the North Sydney Bears.
O'Reilly was the son of athlete Bill O'Reilly, who held a long-standing national record for the hammer throw.
[1] A utility, O'Reilly competed in first-grade for North Sydney from 1926 to 1930, making sporadic appearances as either a three-quarter or lock.
He coached North Sydney to a third grade premiership in 1937, then in 1940 steered them to a reserves premiership.
[2] In the 1942 NSWRFL season, O'Reilly served as North Sydney's first-grade coach.