Leeds United manager Marcelo Bielsa owned up to sending a spy to check on opponents Derby County last week.
His controversial actions have brought plenty of criticism, even though there is no specific FA law against it.
Former Leeds manager Garry Monk weighed in on the furore, and said he was disappointed by Bielsa.
Monk told WalesOnline: "It's not the right thing to do, it's not ethical.
"I suppose it's more disappointing to hear something like that from such an experienced manager and such a world-class manager as he is.
"Once the comical value wears off, in this country we don't see those things as the right things to do."
Monk quit Leeds in 2017 before taking over at Middlesbrough, and is now at Birmingham City, who are ninth in the league.
Leeds are back on track after a tough season last year and sit top of the Championship table with a four point gap.
It remains to be seen if the FA will decide on any punishment against Bielsa or Leeds.