Only the most diehard of Chargers fans could've envisioned a mid-December game at Kansas City as a division showdown.
The Chiefs won their first five and had Super Bowl dreams. The Chargers lost their first four and nobody could remember where they were playing, having moved out of San Diego this season to a soccer stadium in Carson, Calif.
A prime-time game on a Saturday night seemed like a NFL Network mismatch back then. Now the game is for the division lead and inside track to the AFC West title.
"The players know that (when it's) in the last quarter of the season and you're in the mix, every game becomes very important," Chiefs coach Andy Reid said Monday.
The importance of this one increased a notch when both teams won on Sunday. The Chiefs defeated the Raiders 26-15 to end a four-game losing streak and the Chargers hammered Washington 30-13 to extend their winning streak to four games.
Those trends illustrate how the stakes have increased for this game between first-place teams with 7-6 records.
"The atmosphere on Saturday night will be about as good as you can find anywhere," Chargers quarterback Philip Rivers said. "Those are games you grow up dreaming about playing in."
The Chargers have won seven of nine after their miserable start, and Rivers has been on fire. In their four-game winning streak, he's thrown eight touchdown passes and no interceptions.
The Chiefs finally found success, opening a 26-0 lead after three quarters Sunday. A loss wouldn't have eliminated them from playoff contention but it would have been perhaps the most discouraging of the past two months.
Instead, they rose to the occasion to convincingly defeat a division rival and set up Saturday's contest.
"Anytime you have a divisional game, you have to come and play," Chiefs tight end Travis Kelce said. "That's the accountability you have to have."
The AFC West is still a three-team race, even with the Raiders falling to 6-7 on Sunday. And the silver and black caught a break with their remaining schedule.
Oakland plays host to the Cowboys on Sunday and travels to Philadelphia for a Christmas night game. The Eagles will be without quarterback Carson Wentz, who suffered a season-ending knee injury on Sunday.
The Raiders will have to keep winning to maintain pace with the Chiefs-Chargers survivor. That winner will lead the division.
If it's the Chiefs, they'll also own tie-breaker advantages over both of their division rivals. They will have swept the Chargers, and head-to-head is the first tiebreaker. The Chiefs defeated the Chargers in September, 24-10.
Also, with a victory, the Chiefs will have improved to 4-1 in the division. The Chiefs and Raiders split their regular-season games, but with a 2-3 division mark the Raiders couldn't catch Kansas City in the second tiebreaker step.
After Saturday, the Chiefs play at home against the Dolphins and finish the season at the Denver Broncos. The Chargers' final two games are at the New York Jets and at home against the Raiders.
The Chargers haven't won at Arrowhead Stadium since 2013, the last time they won the AFC West and reached the playoffs.
The Chiefs, meanwhile, are gunning for their third straight playoff season and fourth in Reid's five years in Kansas City. Saturday's winner takes a big step toward the title.
