Donald Wayne Barclay III (born April 18, 1989) is a former American football offensive guard.

He played college football at West Virginia and was signed by the Green Bay Packers as an undrafted free agent in 2012.

Barclay attended Seneca Valley Senior High School in Harmony, Pennsylvania.

He played in 52 games, and was named fourth-team All-America and first-team All-Big East in 2011 by Phil Steele’s College Football.

[15] In February 2025, Barclay was named head football coach at his alma mater, Seneca Valley High School.