William L. Reilly (born February 28, 1943, in Long Branch, New Jersey) is an American steeplechase runner who competed in the 1968 Summer Olympics.
Reilly was an All-American runner for the Penn State Nittany Lions track and field team, running on their 5th-place 4 × 800 meters relay relay at the 1965 NCAA indoor track and field championships.
See also List of Pennsylvania State University Olympians
References