LINCOLN, NE – NOVEMBER 12: Place kicker Caleb Lightbourn #35 of the Nebraska Cornhuskers punts against the Minnesota Golden Gophers at Memorial Stadium on November 12, 2016 in Lincoln, Nebraska. (Photo by Steven Branscombe/Getty Images)Caleb Lightbourn spent most of his Nebraska career as the Huskers’ starting punter. Midway through last year, walk-on Isaac Armstrong won the job from him.He remained with the Huskers through the spring. However, he struggled to reclaim the form that had him as the starter to begin his career.Now, Lightbourn will look for opportunities elsewhere. He is entering the transfer portal.Caleb Lightbourn announced his decision via Twitter on Tuesday afternoon.He acknowledged his struggles with the “mental side of the game,” and thanks both Mike Riley and Scott Frost, his two head coaches with the Huskers.GBR 🔴⚪🌽 pic.twitter.com/89ylw5YpKP— Caleb Lightbourn (@4th_n_10) April 16, 2019The transfer portal doesn’t guarantee that Lightbourn will leave, but things seem to be trending that way. It does not appear that he’s graduated, so he will have to sit out a year if he leaves Nebraska, and will then have one season of eligibility remaining.He had his best season in 2017, punting for an average of 42.1 yards, with a NET of 38.9 per punt. In 2018, he had 24 punts for an average of 41.6, but lost his job after two punts that averaged under 30 yards against Wisconsin in early October.Armstrong will be the presumptive starter with Lightbourn gone. William Przystup joins the program from Michigan State, but will sit out a year as a transfer.