If the Chiefs beat the Raiders this afternoon, they are the No. 1 seed in the AFC playoffs regardless of anything that happens tomorrow. But the No. 1 seed won’t necessarily mean home-field advantage throughout the AFC playoffs.
Because of the rules change the NFL voted on yesterday, the Chiefs could still play an AFC Championship Game on a neutral field.
What the Chiefs clinch if they win today is the No. 1 seed, a playoff bye, and a home game in the divisional round of the playoffs against the lowest remaining seed in the AFC.
But it would still be possible for the Chiefs to face the Bills on a neutral field in the AFC Championship Game: If the Chiefs win today and the Bills beat the Patriots tomorrow, then the Bills will have the No. 2 seed in the AFC and would have home games in both the wild card round and the divisional round. If the Bills were to win those two playoff games, and the Chiefs were to win their divisional round games, it would be Chiefs-Bills on a neutral field in the AFC Championship Game.
If the Chiefs win today, the Bills are the only AFC team Kansas City could play on a neutral field. Any other team would have to go to Kansas City in the AFC Championship Game.
If the Chiefs lose today, that opens up the possibility of the Bills earning the No. 1 seed and home-field advantage in the AFC: With a Chiefs loss, the Bills only need to beat the Patriots tomorrow to get the first-round playoff bye and home-field advantage throughout the AFC playoffs, including the AFC Championship Game if the Bills win in the divisional round.
The Bengals are mathematically eliminated from the No. 1 seed and a bye but should still be hoping for a Chiefs loss today. If the Chiefs lose today, the Bengals beat the Ravens on Sunday, and the Bengals end up facing the Chiefs in the AFC Championship Game, that game would be played on a neutral field. Otherwise the game would be in Kansas City.