Iowa vs Top 25

2019 College Football Rankings for Preseason | ESPN

Not seeing Illinois or Nebraska anywhere in the 2019 Final Rankings.
?
They weren't. I just realized that I completely misinterpreted your question. For some silly reason I interpreted it as when was the last time we beat a top 25 team in the last regular season game. I now understand you were asking when was the last time Iowa beat a team that was ranked in the top 25 at the end of the season. Your answer of 2019 Minnesota is correct.
 
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