KANSAS CITY, Mo. -- Andy Reid has an 18-3 career record coming off a bye. The Kansas City Chiefs will have the benefit of that extra week of rest and preparation before their first playoff game.

The 12-4 Chiefs saw to that by holding off the Los Angeles Chargers 31-21 on Sunday at Arrowhead Stadium. That result, coupled with the New England Patriots’ loss to the Miami Dolphins, gives the Chiefs the No. 2 seed in the AFC playoffs and a first-round bye.

The Chiefs will open the postseason in two weeks at Arrowhead against an opponent to be determined. They finished the regular season with a six-game winning streak.

In that sense, beating the Chargers was like winning a playoff game for the Chiefs. It earned them a week off rather than having to go through the grind of preparing for a wild-card game over the upcoming week.

Speed kills: The Chiefs trailed 14-10 until they scored back-to-back touchdowns covering 188 yards: Mecole Hardman's 104-yard kickoff return and Damien Williams’ 84-yard run.

Promising trend: Chiefs special teams coordinator Dave Toub has coached some great return specialists, including Tyreek Hill and Devin Hester, when he was with the Bears. Toub has maintained all season that Hardman had similar ability, even though he lacked a big return. But he finally delivered for the Chiefs in a big moment. His kickoff return gave the Chiefs a 17-14 lead in the third quarter.

QB breakdown: Patrick Mahomes didn’t finish the season with a flourish. Mahomes was 16-of-25 for 174 yards and a touchdown. His 7.0 yards per attempt was his lowest of the season since throwing for a 5.7 average against the Chargers in Week 11 in Mexico City.