William Frye Garcelon Jr. (October 24, 1868 – July 4, 1949) was an American politician, lawyer, college football player, track and field athlete, and coach.

He attended Bates College, where he played football and baseball and was a member of the track team.

In 1893 and 1894, he played football at left halfback for the Boston Athletic Association (BAA).

[3] Around the same time, he was an athletics instructor at Roxbury Latin School in Boston and coached the track team at Portland High School in Portland, Maine.

In 1933, Garcelon was elected president of the Boston Garden and became the head of the BAA in 1934.