What happened: Iamaleava hurt his knee late in the first half at Oregon on a scramble between defenders. He took one more snap and did not return after halftime as Ty Dieffenbach finished the 17-15 win.

Why it matters: UCLA is 5-0 under Bob Chesney in a surprise College Football Playoff push. Losing the starting quarterback forces a midseason offensive reset with an untested depth chart.

What to watch: Chesney must choose between Dieffenbach and sophomore Madden Iamaleava. The starter decision comes before the Wisconsin matchup.