Off the top of my head I think JCC went like 15 yrs. loosing just once before loosing to ODLH. (he lost to Frankie in between)
Maske I think is riding on 18 yrs. having lost just 1 fight.
Joe Louis went 16 yrs. having lost 1 fight.
Bowe went 17 yrs. having lost 1 fight.

But damn! 19 yrs. is a lot of time so he must be old school.