The treasure hunter involved in a heated dispute with USC men’s basketball head coach Eric Musselman on the beach has filed a lawsuit over the altercation, claiming the incident left him in a world of pain.

Gary Gosnell says that after Musselman verbally berated him on the sand in Manhattan Beach on Sept. 13, he’s suffered from “severe emotional and psychological distress” as well as “a significant deterioration of his health,” according to the lawsuit filed in LA Monday and obtained by the California Post.

USC Trojans head coach Eric Musselman yells at a referee during a Big Ten college basketball game between the USC Trojans and the Iowa Hawkeyes. Icon Sportswire via Getty Images

The altercation happened at around 10:30 a.m., after Gosnell sifted through sand near a Trojans men’s basketball team photoshoot while live on his “Gary’s Metal Detecting” YouTube channel, according to the lawsuit.

“A USC assistant coach, who on information and belief is [Will] Conroy, approached Mr. Gosnell and demanded that he move out of the area so that the team could take its photographs,” Gosnell’s lawsuit stated. “Mr. Gosnell explained that he was simply passing through and would move on once he finished what he was doing, noting that it was a public beach and that he could be wherever he wanted to be.”

Trojans men’s basketball head coach Eric Musselman is seen in a video getting into an altercation with a treasure hunter in Manhattan Beach.Trojans men’s basketball head coach Eric Musselman is seen in a video getting into it with a treasure hunter in Manhattan Beach.

Gosnell alleged Conroy then threatened him, before Musselman stepped in.

The Trojans head coach “advanced approximately sixty feet across the sand toward Mr. Gosnell while screaming profanities and came right up to Mr. Gosnell’s face,” Gosnell’s lawsuit alleged. “Musselman shouted at Mr. Gosnell to ‘[s]hut the f—k up,’ called him a ‘f—king d—head,’ and threatened that ‘[s]omebody should f—king drop you ass is what should happen.’”

Gosnell claimed in his suit that the USC coaches only backed away after he told them he was filming the encounter.

Gosnell added that he was afraid throughout the incident because he “was in no position to defend himself against, or to escape from, the coaches and the athletes under their command.”

Gosnell is “a 57-year-old man who has undergone three spine surgeries, a knee surgery, and four foot surgeries,” the treasure hunter’s lawsuit claimed. Gosnell also “holds a disabled person parking placard.”

USC Trojans head coach Eric Musselman reacts during the first half of an NCAA college basketball game against the UCLA Bruins. MediaNews Group via Getty Images

Gosnell, who described himself in the lawsuit as a former correctional officer who’s suffered from post-traumatic stress disorder, is suing Musselman and Conroy, alleging their actions caused him “severe emotional and psychological distress, including fear, anxiety, and humiliation.”

He also said their behavior sparked “a resurgence and aggravation of his PTSD symptoms, including extreme fear, the return of severe and frequent nightmares, persistent hypervigilance, and an intense fear of returning to the beach and of encountering persons wearing USC-branded apparel.”

Gosnell is additionally suing USC, claiming the school should have better supervised Musselman following the alleged “racially charged” incident he had with former Trojans basketball player Chad Baker-Mazara during the 2025-26 season.

USC Trojans head coach Eric Musselman reacts after a play as USC Trojans guard Chad Baker-Mazara (4) looks on during a college basketball game against the Rutgers Scarlet Knights at the Galen Center in Los Angeles, Saturday, Jan. 31, 2026. Icon Sportswire via Getty Images

“USC knew or should have known that Musselman had a propensity to engage in unprovoked, profane, hostile, and intimidating verbal outbursts directed at others,” Gosnell’s lawsuit stated, “and that this propensity created a particular risk that Musselman would verbally abuse, threaten, and intimidate persons with whom he interacted in the course of his duties, including members of the public encountered during team activities.”

Gosnell “brings this action to recover compensatory damages, punitive damages, statutory damages and civil penalties, attorney’s fees, and costs of suit,” the lawsuit stated.

Requests for comment from USC and a rep for Musselman on Tuesday were not immediately returned.

Musselman did previously acknowledge the beach incident after The Post published video of the altercation on Sept. 16.

“I know the responsibilities that come with my role,” Musselman said in a statement, “and while I was trying to step in and support my coach, I definitely should have handled this situation better and will learn from this for the future.”

USC is slated to open its 2026-27 season with an exhibition game against North Carolina in Greensboro on Friday.