Guy Dan "Big Dan" Estes (January 1, 1888 – November 13, 1944) was the head coach of the Central Arkansas college football program from 1915 to 1916 and from 1919 to 1932. He also coached the school's basketball program from 1920 to 1929. Estes also served as coach of the University of Arkansas at Monticello football team in 1917.Estes was an alumnus of the University of Arkansas, where he played football for coach Hugo Bezdek, winning four letters during his tenure.