What happened: Kansas City Chiefs offensive lineman Trey Smith will not return against the Atlanta Falcons due to a concussion. Smith was evaluated for a concussion earlier in the game before the team downgraded him to out.

Why it matters: Smith's departure forces Kansas City to reshuffle its interior offensive line protection during Sunday's contest against Atlanta. The starting guard anchors the Chiefs' front line, making his absence a significant test for the unit's depth.

What to watch: Smith will have to clear the NFL's concussion protocol before being cleared to return to team activities.