The Kansas City Chiefs (2-3) take on the divisional-rival San Diego Chargers (5-1) on Sunday as they fight to get back to the .500 mark. 

"We look forward to the challenge of playing the Chargers," Chiefs coach Andy Reid said. "They're a good football team. We know that and it's important that we get ourselves ready and prepare to play."

The Chargers are coming off a four-point win over the Oakland Raiders last week, and while their five wins has them tied for best in the NFL, the combined record of the teams they've beaten for those victories is just 7-21.

The combined record for the Chiefs opponents this year is 16-12.

It's impossible to talk about the Chargers and not start with quarterback Philip Rivers.

He's leading the NFL with a 117 quarterback rating, ranks third in passing yards with over 1,700 and has 15 touchdowns to just two interceptions.

The Chargers passing offense has seen 28 completions of 20 yards or more, which leads the NFL. They rank third in the NFL in yards after the catch with 766.

Simply put, Rivers is at his best when the ball is out of his hands quickly.

According to ProFootballFocus.com, Rivers is completing 78.4 percent of his passes when he throws the ball in 2.5 second or less, but when he's holding it for 2.6 seconds or longer, that completion percentage drops to 59.8 percent and he's in the middle of the pack.

Between 2011 and 2012, Rivers threw 35 interceptions and fumbled the ball 20 times.

But last year, Mike McCoy's first year as the head coach in San Diego, Rivers got back to the player most of us have seen throughout his nine years as the Chargers starting quarterback. 

"I thought [Rivers] and Norv Turner [Chargers head coach 2007-12] had a really great relationship and put up big numbers and played very well together," Reid said. "I think he's done the same with Mike (McCoy). I think he's really taken on this offense. It's a new challenge late in his career. 

"It's different than what he's done before and I think he's taken on that with—I'm not going to say new energy, its new for him so I guess we could probably put it in that category."

Rivers' top targets this season have been receivers Malcom Floyd, who leads the team with 362 yards receiving, Eddie Royal, who has 325 yards on 22 receptions with five touchdowns, and Keenan Allen, the second-year receiver who leads the team with 28 receptions.

Finally, one of Rivers' favorite targets throughout his career has been 34-year-old tight end Antonio Gates, who once again is lighting it up this season with six touchdown receptions, which ranks third in the NFL. 

At running back, the Chargers have seen a lot of turnover with injuries to starters Ryan Mathews and the "do a little bit of everything" player in Danny Woodhead.

But it's been an undrafted rookie from Buffalo, Branden Oliver, who has stepped up for their offense, rushing for more than 100 yards in each of their last two games.

Overall, the Chargers haven't had a lot of success rushing the football. They rank last in the NFL in percentage of rushes that go for at least four yards at just 31.6 percent. It's an offense that lives and dies with Rivers, and that's been working for them so far this season.

They average 27.2 points per game, which ranks fifth in the NFL.

Along the offensive line, the Chargers are on their third center this season.

Veterans Nick Hardwick (neck) and Doug Legursky (knee) were put on IR, and the 6-foot-2, 300-pound Rich Ohrnberger has stepped in to hold down the center position for the Chargers.

For the Chiefs, 6-foot-3, 346-pound nose tackle Dontari Poe will be counted on again to do what he does best: wreak havoc in the center of the opposing offensive line. 

On the defensive side of the ball, the Chargers boast the NFL's No. 2 ranked scoring defense, giving up just 15.2 points per game. They're fourth in giveaway-takeaway ratio at plus-seven, intercepting four passes and causing five fumbles along the way.

"They're a good unit," Chiefs quarterback Alex Smith said of the Chargers defense. "They do a lot defensively scheme-wise, they play about every coverage, front, bring all the pressures. So it's hard to get a beat on them, they do so much, they play fast.

"I think they collectively, they get to the football. Those 11 guys, they do a good job of that so it'll be a big challenge for us."

The Chargers have 10 different players who have recorded at least one sack. They rank in the Top 10 in both passing (fourth at 209 ypg) and rushing (ninth at 99 ypg) defense.

The Chiefs have already faced some of the premier pass rushers in the NFL in the Titans' Jurrell Casey, Patriots' Chandler Jones, Dolphins' Cameron Wake and Broncos' DeMarcus Ware and Von Miller.

Chargers defensive coordinator John Pagano might not have one pass rusher lighting up the stat sheet through six games, but he's creative in the ways he brings pressure on an opposing quarterback.

One player who is very familiar to Chiefs fans is cornerback Brandon Flowers, who hasn't practiced yet this week for the Chargers after suffering a groin injury in their win over the Raiders.

"I think he's playing good football," Reid said of Flowers. "He played good football here; he's playing good football there. He's a smart kid and good player."

Chiefs quarterback Alex Smith agreed with Reid's assessment of Flowers.

"He's playing good, they're whole secondary I think is playing good football," Smith said. "But certainly he is playing well. He got beat the one time last week earlier in the game, but other than that, he's played really, really good football."

According to Pro Football Focus, Flowers has been the best cornerback in the NFL through six games. One area the Chargers defense has struggled this season has been in the red zone, where they rank last in the NFL, giving up touchdowns on 75 percent of drives that get into the red zone.