| Week | Rank | Rate | Record | SOS | Opponent | Score | Rank Then | Rank Now |
| 1 | 40 | 0.000 | (0,0) | 0.000 | --bye-- |
| 2 | 29 | 0.500 | (1,0) | -0.500 | Nebraska | 13 to 10 | 424 | 81 |
| 3 | 42 | 4.965 | (2,0) | 3.965 | Eastern Michigan | 25 to 6 | 79 | 176 |
| 4 | 14 | 2.535 | (2,1) | 2.202 | North Carolina | 13 to 31 | 2 | 41 |
| 5 | 74 | 1.557 | (2,2) | 1.557 | Northwestern | 34 to 37 | 58 | 35 |
| 6 | 60 | 1.584 | (3,2) | 1.384 | Louisiana-Lafayette | 35 to 24 | 146 | 145 |
| 7 | 52 | 1.691 | (3,3) | 1.691 | Michigan | 10 to 52 | 6 | 2 |
| 8 | 46 | 1.668 | (3,3) | 1.668 | --bye-- |
| 9 | 36 | 1.757 | (4,3) | 1.614 | Iowa | 12 to 10 | 18 | 16 |
| 10 | 33 | 1.846 | (5,3) | 1.596 | Michigan St | 27 to 12 | 107 | 72 |
| 11 | 46 | 1.670 | (5,4) | 1.559 | Illinois | 26 to 27 | 55 | 73 |
| 12 | 53 | 1.547 | (5,5) | 1.547 | Purdue | 30 to 49 | 73 | 83 |
| 13 | 58 | 1.502 | (5,6) | 1.592 | Ohio State | 3 to 37 | 2 | 7 |
| 14 | 65 | 1.480 | (5,7) | 1.647 | Wisconsin | 14 to 28 | 46 | 53 |
| 15 | 65 | 1.394 | (5,7) | 1.561 | --bye-- |
| 16 | 67 | 1.391 | (5,7) | 1.558 | --bye-- |
| 17 | 67 | 1.367 | (5,7) | 1.533 | --bye-- |
| 18 | 61 | 1.418 | (6,7) | 1.495 | Bowling Green | 30 to 24 | 94 | 94 |
| 19 | | | | | --bye-- |
| 20 | | | | | --bye-- |