William Clay Matthews Sr. (August 1, 1928 – March 23, 2017) was an American professional football lineman and patriarch of the Matthews family of football players.

Matthews played for four seasons with the San Francisco 49ers of the National Football League (NFL), the first in 1950.

When the Korean War broke out, Matthews enlisted as a paratrooper for the Army's 82nd Airborne Division.

He was selected by the Los Angeles Rams in the 25th round of the 1949 NFL draft before being traded to the 49ers.

[4] Matthews died at the age of 88 on March 23, 2017, in Mount Pleasant, South Carolina.