Harrell has been diagnosed with a torn ACL, Jim Wyatt of the Titans' official site reports.
Harrell's injury occurred during Thursday's preseason win over San Francisco. Per Turron Davenport of ESPN.com, the third-year linebacker will be sidelined for the entire 2026 season. It's a tough blow for Harrell and Tennessee's defense after the Michigan product showed intriguing growth with 3.5 sacks over his final four games during his 2025 sophomore campaign. He'll now look to rehab in the hope of being ready for training camp ahead of the 2027 season.