McDonald joined the Chiefs as an undrafted free agent in 2025 following his final college season at TCU. He appeared in all 17 games as a rookie, recording 25 combined tackles (10 solo and 15 assists).
Kansas City opened the 2026 season with a 31-10 win over the Denver Broncos on Monday night, but the victory came with defensive injuries. McDonald left the game with a knee injury and did not return, raising early concerns about the Chiefs’ depth at linebacker.
McDonald was placed on the Reserve/Injured List, meaning he will miss at least four games before he can be considered for a return.
The injury occurred during the season opener against Denver. He played limited defensive snaps before leaving the game, finishing with one assisted tackle.
This development comes as Kansas City faces several defensive concerns. McDonald’s absence temporarily thins a unit that had begun to rely on him as a starter at linebacker. With him out, the Chiefs will lean on other players such as Nick Bolton, Drue Tranquill, Jeffrey Bassa, and Jack Cochrane to fill the rotation.
The Chiefs’ injury situation in Week 1 also included other defensive blows. Rookie cornerback Mansoor Delane exited the Denver game with a shoulder injury, though head coach Andy Reid indicated Delane had a strong chance to play in Week 2. Safety Chamarri Conner is also dealing with a knee issue.
To adjust the linebacker rotation during McDonald’s absence, Kansas City promoted fullback Ben VanSumeren to the active roster as part of recent roster moves, providing an additional option for Week 2 preparation against the Colts.
