Phil Woosnam, a former Welsh international and former coach of USA national team, has died at age 80, the US Soccer Federation announced on Sunday.
Woosnam, who was also a former commissioner of the North American Soccer League during the height of its popularity in the 1970s, died from complications related to prostate cancer and Alzheimer's disease.
"We are saddened by the loss of one of the most important individuals in the history of American soccer," US Soccer president Sunil Gulati said.
"The impact that Phil Woosnam had in the growth of soccer in the United States was immense. He was a giant in the sport and his leadership, passion and knowledge will be missed."
He also served as the NASL commissioner from 1968 to 1982, including the period when the New York Cosmos brought together Pele and other global stars to bring the sport a US profile it has only in recent years managed to rival.