Peat, a former four-star player, played sparingly in 2012, his redshirt freshman season.
The Arizona native missed spring practices with a back injury and was left off the 105-man roster heading into fall camp after gaining a significant amount of weight and being out of shape. At the time, he said it was a huge wake up call.
"I learned I needed to take responsibility for myself and that there were things I needed to take care with no excuses – back problems or not," said Peat.
Nebraska is expected to take a full class in the 2013 recruiting class, but Peat's departure opens up another scholarship for down the road.