He then played professional football as an end for the Dayton Triangles in the NFL. He appeared in 31 NFL games, 28 as a starter, from 1920 to 1923. He also played at the center position for the Triangles in 1916 and 1917, prior to the formation of the NFL. He was described as "one of the best all-round athletes ever developed in this city."
Later years
After retiring from football, Thiele went into the automobile business. He died in 1986 in Dayton.