Nwosu attended and played college football at USC under head coachesSteve Sarkisian and Clay Helton. After playing in 12 games during his freshman season, Nwosu was not able to participate in the 2014 Holiday Bowl due to unspecified team rules violations. It was later reported that Nwosu did not enroll in the following spring semester. Despite speculation that he may leave the team, Nwosu was able to take summer classes and rejoin the team for the 2015 season. After his senior season at USC, Nwosu was named a co-MVP of USC along with quarterback Sam Darnold. He was also on the watchlist for the Butkus Award. Following his senior season, he participated in the 2018 Senior Bowl.
Professional career
The Los Angeles Chargers selected Nwosu in the second round of the 2018 NFL Draft. Nwosu was the sixth linebacker drafted in 2018. He will be playing in his hometown of Carson at the temporary home of the Chargers at the StubHub Center. On May 13, 2018, the Los Angeles Chargers signed Nwosu to a four-year, $5.75 million contract that includes $3.01 million guaranteed and a signing bonus of $2.26 million. Nwosu enteredtraining camp slated as a backup outside linebacker. Head coachAnthony Lynn named Nwosu the backup strongside linebacker to start the regular season, behind veteran Kyle Emanuel. He made his professional regular season debut in the Los Angeles Chargers’ season-opening 38-28 loss to the Kansas City Chiefs. On September 16, 2018, Nwosu recorded three combined tackles and made his first career sack during a 31–20 victory at the Buffalo Bills in Week 2. Nwosu made his first career sack on Bills’ quarterback Josh Allen for a three-yard loss in the first quarter. As the Chargers made the playoffs, they faced off against the Baltimore Ravens in the Wild Card round. Nwosu made a critical play at the end of the game, forcing Ravens quarterback Lamar Jackson to fumble on what would have otherwise been a potential game winning drive for the Ravens. The Chargers recovered the fumble, sealing a 23–17 win to advance to the Divisional round. Nwosu finished the 2019 season with 31 tackles, two sacks, and three passes defensed.
