They again retreated to the locker room at the Rose Bowl on Saturday with various injuries.
In the first half, inside linebacker Kenny Young left with what was later described as an upper body injury.
In the second half, his replacement, Josh Woods, a freshman who had been on track to redshirt this fall, exited the game as well due to a hamstring injury.
The battered Bruins held on for a 35-31 win over Colorado, but they also saw their defensive depth continue to shrivel.
“We’re just continually trying to rearrange the puzzle and put it back together the best that we can,” Coach Jim Mora said Sunday.