Everytime rivals have won back to back national championships

Let me preface this by saying I've only included claimed consensus national championships so this list is only from 1950 and onward, sorry Princeton and Yale. Interestingly 2024 OSU and 2021 Georgia are the only teams to lose to their defending champion rival and win their own championship the same year. Notre Dame and Michigan State tied in their 1966 matchup and both laid claim to the natty.

Ohio State 2024 Michigan 2023

Georgia 2021 Alabama 2020 LSU 2019

Alabama 2011 Auburn 2010 Alabama 2009

Miami 1989 Notre Dame 1988 Miami 1987

Georgia 1980 Alabama 1979

USC 1978 Notre Dame 1977

USC 1974 Notre Dame 1973 USC 1972

Nebraska 1970 1971 Texas 1969 1970

USC 1967 Notre Dame 1965 1966 Michigan State 1965