After graduating from Sanger, Mosby committed to Fresno State University and played in every game as a true freshman, mainly as a special teamer. He made a total of five tackles in 14 games. As a sophomore in 2018, Mosby recorded 12 tackles and one interception while appearing in 13 out of 14 games. His one interception was returned 95 yards for a touchdown against San Jose State and was the fourth-longest in team history.[1]
Mosby recorded 78 tackles as a junior in 2019, placing fourth on the squad. He appeared in all 12 games, and 40 of his tackles were solo stops. In a 2020 season shortened by COVID-19, Mosby played in all six games and recorded 21 tackles, including three for a loss. All players were given an extra year of eligibility because of the virus, and he opted to return to the team in 2021 as a fifth-year player. Playing defensive end, Mosby started 12 games out of 13 and was named an honorable mention All-Mountain West Conference. He recorded 40 tackles, six sacks, six forced fumbles, two recoveries, and a team-leading 15.5 tackles-for-loss. He was invited to the Hula Bowl and the NFLPA All-Star Game after the season ended.[1]
After going unselected in the 2022 NFL draft, Mosby was signed by the Carolina Panthers as an undrafted free agent.[3] He was waived at the final roster cuts, but was later re-signed to the practice squad.[4][5] He was elevated to the active roster for their week one game against the Cleveland Browns,[6] and their week two game against the New York Giants,[7] and made his debut in the latter, appearing on 16 special teams snaps.[8] He was signed to the active roster on September 21,[9] and spent one week there before being waived on September 26,[10] after which he was re-signed to the practice squad.[11] He was promoted back to the active roster on October 15.[12] He was waived on November 19 and re-signed to the practice squad.[13] He signed a reserve/future contract on January 9, 2023.[14] He was waived on August 1, 2023.[15]
Green Bay Packers
On August 3, 2023, Mosby was claimed off waivers by the Green Bay Packers.[16] He was released on August 29.[17] A day later, he was signed to the Packers' practice squad.[18] He signed a reserve/future contract on January 22, 2024.[19]
On August 24, 2024, in the preseason finale against the Baltimore Ravens, Mosby strip-sacked rookie quarterback Devin Leary, which was recovered by teammate Anthony Johnson Jr. for a touchdown. On the very next drive, he picked off Leary on a short pass. His performance ultimately landed him a spot on the Packers' initial 53-man roster ahead of the season.[20][21]
