Agent Brett Tessler announced the new deal Monday that ensures the running back from New Smyrna Beach High will report to camp with his teammates this week.
“Happy we got things worked out and looking forward to him having another great season there,” Tessler wrote on Twitter. “Thanks to the organization for taking care of him.”
Tessler had made a public trade demand on July 8 after talks with the 49ers failed to lead to a new deal to replace the three-year contract Mostert signed in 2019 when he was still mostly a special-teams standout.
Mostert is due $2.