Phil Woosnam, the former Welsh soccer star who served as the North American Soccer League’s commissioner and had a brief stint as coach of the U.S. national team, died July 19 in Marietta, Ga. He was 80.

U.S. Soccer said Mr. Woosnam died of complications related to prostate cancer and Alzheimer’s disease.

“The impact that Phil Woosnam had in the growth of soccer in the United States was immense,” U.S. Soccer President Sunil Gulati said in a statement. “He was a giant in the sport and his leadership, passion and knowledge will be missed.”

Mr. Woosnam played for a number of pro clubs, including English teams Aston Villa, West Ham and Leyton Orient, during a 16-year career. He also earned 17 caps with the Welsh national team.

He came to the United States in 1966 at age 35 and became the U.S. coach in 1968, serving in the role for nine games, including four World Cup qualifiers.

North American Soccer League Commissioner Phil Woosnam (AP Photo/RF)

He won the North American Soccer League’s first coach of the year award while leading the Atlanta Chiefs in 1968 before taking over as commissioner, a position he held until 1982. Under his guidance, the NASL brought in world-class players such as Pelé. The league folded after the 1984 season.

Mr. Woosnam, the cousin of pro golfer Ian Woosnam, was inducted into the National Soccer Hall of Fame in 1997.

— Associated Press