Chiefs' Tyrann Mathieu Diagnosed with Quad Contusion After Injury vs. Steelers

Kansas City Chiefs safety Tyrann Mathieu suffered a left quad contusion during Sunday's 36-10 victory over the Pittsburgh Steelers, head coach Andy Reid told reporters.

Mathieu exited the game during the second half and was ruled out as Kansas City held a commanding 33-3 lead.

The veteran safety was an All-Pro for the second time in 2020. With free agency looming in the offseason, he had a strong incentive to put together another standout season in 2021.

Through 13 games, Mathieu isn't quite reaching the same heights he did one year ago. He has 65 total tackles, six pass breakups and three interceptions, including a pick-six in Kansas City's Week 2 loss to the Baltimore Ravens:

Following a brutal start, the Chiefs defense has leveled off a bit. The unit is allowing 366.4 yards per game, 25th in the NFL. Considering Kansas City surrendered 400-plus yards in four of its first five games, its current position represents an improvement.

But losing Mathieu is a setback the two-time reigning AFC champions don't need as they've righted the ship following a 2-3 start and control their destiny for home-field advantage in the playoffs. There isn't another player in their secondary who can fill all of the duties he serves in a given game.