The LA Chargers had one of the worst run defenses in league history in Brandon Staley's first season. Staley's defense was bad throughout his tenure with the Bolts and it was shocking how bad the run defense was in his first season.
To fix this problem, the Chargers signed a pair of run stuffers in the 2022 offseason. Staley reunited with Sebastian Joseph-Day with a three-year deal while Austin Johnson signed a two-year deal after a solid season with the New York Giants.
Joseph-Day was a cap casualty candidate and the Chargers made that decision early, waiving him a week after Staley was fired. SJD then signed with the San Francisco 49ers to get a chance to contend for a second Super Bowl ring.
Johnson finished out the season with the Chargers but his fate is ultimately going to be the same. The Chargers have absolutely no reason to re-sign Johnson as the young options on the roster are already better than Johnson is at this point in his career.
Johnson never quite produced what the Chargers needed him to produce as his second season was sluggish and his first season ended early due to an injury. Thankfully, it was not a huge signing so the Chargers didn't waste much salary cap space.