ESPN NFL

SAN DIEGO -- Quarterback Matt Cassel didn't travel to San Diego after having an emergency appendectomy on Wednesday.

It looked like the rest of the Kansas City Chiefs stayed home, too.

Philip Rivers threw two touchdown passes to Malcom Floyd and the Chargers remained alive in the AFC West race with a 31-0 win Sunday over the division-leading Chiefs, who went nowhere without Cassel.

The Chiefs were such a non-factor that they were held to 67 yards, the second-fewest in their history, and suffered their first regular-season shutout loss to the Chargers. The teams began play in 1960 as members of the AFL.

"Defensively, I'm not sure that you could play any better than that," said Chargers coach Norv Turner, who gave game balls to the offensive and defensive lines.

The four-time defending division champion Chargers (7-6) pulled within one game of the Chiefs (8-5). A loss would have eliminated the Bolts from the division race.

After getting outmuscled in a 28-13 loss to Oakland last Sunday, the Chargers were handed two gifts. The first was hearing that Cassel had undergone an emergency appendectomy and that they'd likely be facing backup Brodie Croyle.

The second was the Raiders' loss at Jacksonville earlier Sunday, which dropped the Raiders to 6-7.

"It's a playoff game and we can't lose," Rivers said. "We know that. We can't look to January because there's no guarantee we are going to get there. But it's playoff football from here on out, and it still may not be enough."

Croyle completed 7 of 17 passes for 40 yards and was sacked four times in his first start since the 2009 opener.

The Chargers outgained the Chiefs 426 yards to 67. San Diego allowed only five first downs -- one in the second half -- to tie its team record.

"When we're on top of our game," we're pretty good," defensive tackle Antonio Garay said. "We backed ourselves into a corner earlier in the season, had a couple of mishaps here and there. One thing that everyone knows about this team is that we're going to fight until the end."

Chiefs running back Jamaal Charles, third in the NFL with 1,137 yards rushing coming in, was held to 40 yards on 10 carries.

"We know their defense is not all that good, but hey, they came through today and stopped us," Charles said.

Rivers was 18 of 24 for 226 yards.

The Chargers ran for a season-high 207 yards a week after being held to 21 in a 28-13 loss to Oakland.

Darren Sproles bounced back from a concussion to catch five passes for 51 yards and run six times for 53 yards. Fullback Mike Tolbert gained 66 yards on 16 carries and scored once, and rookie Ryan Mathews had 65 yards on 16 carries and a score.

"These backs were tackle-breaking machines," Chiefs coach Todd Haley said. "Each one of them, although not with a ton of carries, had broken a lot of tackles. We had to have a great tackling game and we didn't do that."

Said Chargers right tackle Jeromey Clary: "They've got fresh legs and they're all different styles of runners. Mike Tolbert is the bowling ball, Mathews is the bowling ball with a little bit more speed than Tolbert and Sproles is just good speed. They're tough to prepare for."

The Chargers are above .500 for only the second time this season. It was their first shutout since winning 27-0 at Oakland on Sept. 11, 2006.

The Chiefs were shut out for the first time since a 34-0 loss at Carolina on Oct. 5, 2008. They had only 16 yards and one first down in the second half. Croyle dropped to 0-10 as an NFL starter.

"I think if Cassel played we were going to play great anyway," Chargers safety Eric Weddle said. "That was just our mentality. Maybe they would have put up a little more yards, but I don't think one guy would have made a difference in a 31-0 game."

The Chiefs didn't put up a fight.

Rivers led the Chargers to a 21-0 halftime lead. He threw a 17-yard touchdown pass to Floyd on San Diego's first drive and hit him again with a 9-yard TD pass with 40 seconds before halftime. In between, Tolbert ran 8 yards untouched for a touchdown midway through the second quarter.

The Chiefs, meanwhile, were outgained 256 yards to 51 yards in the first half and had only four first downs compared to San Diego's 17.

Rivers was intercepted and lost a fumble on consecutive drives in the third quarter.

Nate Kaeding kicked a 48-yard field goal Mathews scored on a 15-yard run in the fourth quarter.

It was the Chiefs who started the Chargers out on what's been a mediocre season by beating San Diego 21-14 on Sept. 13. Rookie Dexter McCluster returned a punt a team-record 94 yards for a touchdown, the first of many special teams blunders by the Bolts.

The Chargers more than returned the favor.

"I think what's critical for our team is that when you have a devastating, critical loss at a big moment in your season, you can use that to make you work harder, more diligently and stick together," Haley said.

Game notes

The Chiefs gained 16 yards on 19 plays in the second half. ... Chargers LB Brandon Siler sustained an injury to his ribs and DE Jacques Cesaire had a knee injury. ... The Chargers' last home shutout was 26-0 against Indianapolis in 1992. ... The Chargers' only other shutout against the Chiefs was a 17-0 wild-card win following the 1992 season.