The Kansas City Chiefs ended San Diego's postseason hopes in last year's finale, but its first matchup with the Chargers this season comes against a team that's well out of playoff contention.
The surging Chiefs will try to send their AFC West rivals to a sixth consecutive loss while earning their fourth straight win Sunday.
San Diego needed only a win at Kansas City on Dec. 28, but lost 19-7 to finish 9-7 and one game behind Baltimore for the AFC's final berth. The Chiefs also finished 9-7 but needed losses from two other teams to make the postseason.
Kansas City didn't help its chances this season with a 1-5 start, but three consecutive wins have moved it within one game of Buffalo for the last spot.
The Chiefs (4-5) had arguably their best defensive performance in a 29-13 victory in Denver last Sunday. They recorded a season-high five interceptions - four off Peyton Manning that led to his benching in favor of Brock Osweiler.
The Chiefs also recorded five sacks - giving them 11 in the past two games - while allowing 69 rushing yards and 221 total.
"I felt like we've taken it up a notch there for whatever reason there is," coach Andy Reid said.
Alex Smith extended his streak of pass attempts without an interception to 228 - six shy of topping Steve DeBerg's team record from 1990 - and Charcandrick West continued to fill in admirably for the injured Jamaal Charles.
West caught an 80-yard touchdown and had his third rushing score in as many games while facing one of the league's top defenses. He's averaged 92.0 yards on the ground and 137.3 all-purpose yards in the past three contests.
"He does take like twice as many steps, but he can scoot. He's got those little, short legs. But he can go and we knew that," Reid said. "He hadn't had that opportunity to do that, but you got to see it there."
The Chargers gave up a season-worst 446 yards and 337 through the air in a 22-19 loss to Chicago on Nov. 9. San Diego (2-7) has dropped its past five games by an average of 5.0 points.
"Our record is what it is," coach Mike McCoy said. "We can only control the future and the future is now."
The Chargers have dealt with a number of injuries, especially on the offensive line. Their bye week might have given guard Orlando Franklin a chance to heal from a knee injury.
Franklin, signed away from Denver in the offseason with a five-year deal, has missed five games after sitting out once in his first four seasons. Left tackle King Dunlap missed the Bears game because of an ailing ankle, and center Chris Watt was placed on injured reserve with a shoulder injury.
Wide receiver Malcom Floyd reportedly tore the labrum in his shoulder against Chicago and will try to play through the injury. San Diego is already missing its leading pass catcher, Keenan Allen, because of a lacerated kidney.
"We're not going to make excuses here. We're going to keep on plugging every day, work extremely hard, put great plans together. It's not due to a lack of effort," McCoy said. "We've got to finish at the end of the game or make those plays during the game to go up by two scores."
The Chiefs sacked Philip Rivers a career high-tying seven times in last season's finale with Justin Houston getting four. Houston has 7 1/2 sacks this season and a combined 3 1/2 in his last two games.
Rivers has managed to stay upright most of the time lately despite his makeshift line. The Chargers have given up four sacks in the last three contests.
Rivers just missed extending his team-record streak of 300-yard games to six against the Bears, finishing with 280. He has 2,143 yards, 14 touchdowns and three interceptions in the past six contests.
Rivers had two TDs and three interceptions against Kansas City in 2014 as the Chiefs swept the season series. He had won 11 of his previous 13 matchups.
Kansas City ended a six-game losing streak in San Diego on Oct. 19, 2014, as Cairo Santos made a last-minute field goal in a 23-20 victory.
San Diego hasn't dropped six in a row since Oct. 23-Nov. 27, 2011.