Kansas City did just that.
Chiefs rookie kicker Cairo Santos nailed a 48-yard field goal with 21 seconds remaining, giving the Chiefs a 23-20 lead, then Chiefs safety Kurt Coleman intercepted Philip Rivers to send San Diego its second loss of the season.
With the loss, the Chargers fall to 5-2, giving the Broncos a brief 4-1 lead in the AFC West. The Broncos play the San Francisco 49ers on Sunday Night Football tonight; if they win, they will maintain their AFC West lead. If they lose, they'll have to win it back from the Chargers next week.
In fact, whether they win or lose tonight, Denver's Thursday night game against the Chargers is still just as important. If the Broncos win tonight and then still fall to the Chargers next week, they'd still lose control of the AFC West to San Diego, who would be 6-2 to Denver's 5-2. San Diego would also own the head-to-head tiebreaker over the Broncos.
So not a lot changes; next week is still for first place in the AFC West. But if the Broncos win two in a row, they will be sitting very comfortably atop the AFC West, primed for their fourth straight division title, thanks to their hated division rival, the Chiefs.