Stumpf was infamous for his role as the referee who by accusation manipulated the outcome of 22 March 1986 championship match between BFC Dynamo and 1. FC Lokomotive Leipzig which ended in a 1–1 draw that helped BFC Dynamo winning its eighth consecutive national title.
Stumpf was infamous for his role as the referee in the 22 March 1986 championship match between BFC Dynamo and 1. FC Lokomotive Leipzig, where he allegedly manipulated the outcome through accusations, resulting in a 1–1 draw that contributed to BFC Dynamo's national title.