KANSAS CITY, Mo. — Murphy's Law could be applied to Kansas City Chiefs quarterback Matt Cassel.

Anything that could go wrong did go wrong for Cassel and his Chiefs teammates during a 37-20 setback to the San Diego Chargers on Sunday afternoon at Arrowhead Stadium.

The Chiefs (1-3) committed five of their six turnovers in the first half alone — three interceptions by Cassel and two lost fumbles by Jamaal Charles — and never could recover after trailing 27-6 at halftime.

"We've got to solve it and solve it quick," Cassel said. "Turnovers have been killing us and I, myself, have to take better care of the ball.

"Obviously, it starts with me. The whole team, I mean the whole offensive unit, just needs to do a better job of taking care of the ball. We talk about it, but we've obviously got to do a better job when it comes to game time."

After San Diego (3-1) opened with a 76-yard scoring drive for a 7-0 lead, the Chiefs turned the ball over on their first two offensive drives and before anyone could settle into their seat, the Chargers owned a 17-0 lead with 5:28 still remaining in the first quarter.

Kansas City entered the game leading the NFL with an average of 441.7 yards in total offense through its first three games, including a 191.7 rushing average and a 250.0 passing average.

Against the Chargers, the Chiefs simply self-destructed.

Cassel threw an interception on the Chiefs' third play from scrimmage, with San Diego's making the pick at the 28, setting up a 24-yard Nick Novak field goal for a 10-0 lead.

Charles, who was coming off a 233-yard rushing performance, including a team-record 91-yard touchdown run, during a 27-24 overtime win over the New Orleans Saints last week, then fumbled the ball away on his first carry after the ensuing kickoff. Inside linebacker Takeo Spikes stripped the ball loose from Charles and outside linebacker Shawn Phillips recovered the fumble at the San Diego 5-yard line.

After former Chiefs running back Jackie Battle scored on a 1-yard plunge, the Chargers were in command at 17-0.

"I can't speak for anybody else," Charles said. "I just know that I have to put two hands on the ball and I can't put the ball on the ground.

"We lost, and I helped my team to lose."

Down 20-0 after a Novak 47-yard field goal, Charles had a 37-yard touchdown run to trim the margin to 20-6 with 5:09 left in the second quarter.

But Chargers linebacker Donald Butler's 21-yard interception return of a Cassel pass, intended for tight end Tony Moeaki, gave the Chargers a 27-6 lead at the 2:51 mark before halftime.

The Chiefs drove to the San Diego 22 after the ensuing kickoff, but Cassel's pass, intended for wideout Dexter McCluster in the left flat, was intercepted by Chargers cornerback Antoine Cason.

The Chiefs committed their sixth miscue after halftime, when running back Shaun Draughn fumbled the ball away.

Charles finished with 92 rushing yards in 17 carries. He also caught a 13-yard scoring pass, coming out of the backfield, at the 8:40 mark in the third period. 

Chiefs wide receiver Dwayne Bowe had seven receptions for 108 yards, including a 29-yard scoring reception with 5:29 remaining in the fourth quarter. 

• RING OF HONOR — Former Kansas City offensive lineman Will Shields became the 42nd player to be named to the Chiefs Hall of Fame, when he was formally introduced during halftime. … Shields was a third-round (74th overall) pick of the Chiefs in the 1993 NFL Draft. An All-America selection out of Nebraska, Shield played in the NFL from 1993 to 2006 — all with the Chiefs — becoming a 12-year Pro Bowl selection. … Shields started 231 straight games, including playoff games, and had the second-longest active consecutive starting streak in league, behind Brett Favre of the Minnesota Vikings, when he retired after the 2006 season.

• SERIES — It was the 105th meeting between the Chiefs and Chargers. The only team the Chiefs have played more than the Chargers is another AFC West rival, the Oakland Raiders (106). … The Kansas City-San Diego series is now tied at 52-52-1 (.500), although the Chargers have won eight of the last 10. … The Chiefs hold a slim 23-19 advantage in games played at Arrowhead.

NATIONAL FOOTBALL LEAGUE

Sunday

At Kansas City, Mo.
Arrowhead Stadium

San Diego 37, Kansas City 20
                        1     2     3     4       F
San Diego      17    10    0    10 — 37
Kansas City     0      6    7     7  — 20

SCORING SUMMARY
First Quarter
SD — Royal 4 pass from Rivers (Novak kick), 10:04.
SD — FG Novak 24, 6:26.
SD — Battle 1 run (Novak kick), 5:28.
Second Quarter
SD — FG Novak 47, 8:09.
KC — Charles 37 run (pass failed), 5:09.
SD — Butler 21 interception return (Novak kick), 2:51.
Third Quarter
KC — Charles 13 pass from Cassel (Succop kick), 8:40.
Fourth Quarter
SD — Battle 4 pass from Rivers (Novak kick), 7:54.
KC — Bowe 29 pass from Cassel (Succop kick), 5:29.
SD — FG Novak 45, 1:56.
A — 69,979.

TEAM STATISTICS
                                  SD    KC
First downs                  19    25
Total Net Yards           293    353
Rushes-yards        34-104    22-119
Passing                     189    234
Punt Returns              1-0    3-39
Kickoff Returns         2-53    4-109
Interceptions Ret.     3-73    1-1
Comp-Att-Int       18-23-1    24-42-3
Sacked-Yards Lost    3-20    2-17
Punts                    5-53.8    4-51.3
Fumbles-Lost              2-0    4-3
Penalties-Yards         7-75    9-80
Time of Possession   33:52    26:08

INDIVIDUAL STATISTICS
RUSHING — San Diego, Mathews 14-61, Battle 15-39, McClain 2-4, Rivers 3-0. Kansas City, Charles 17-92, Gray 1-15, Draughn 4-12.
PASSING — San Diego, Rivers 18-23-1-209. Kansas City, Cassel 24-42-3-251.
RECEIVING — San Diego, Battle 4-42, Gates 3-59, Brown 3-50, Royal 3-16, Floyd 2-23, Mathews 2-21, McClain 1-(minus 2). Kansas City, Bowe 7-108, Baldwin 4-50, Draughn 4-34, Charles 3-23, Moeaki 3-18, McCluster 2-6, Breaston 1-12.