Over the past two games, the Raiders' run defense has been shredded by the Cowboys and Jets.On Sunday, it will have to stop Jamaal Charles and the Chiefs.It's a matchup that doesn't look promising.Charles is the NFL's third-leading rusher with 1,161 yards and 10 touchdowns. The Chiefs love to use Charles to batter defenses. He's averaging 4.9 yards per carry and is coming off his biggest game of the season, a 150-yard rushing day vs. Washington in a 45-10 victory. Six times this season, Charles has 90 or more yards on the ground.In the first meeting between these teams back in October, Charles had 128 yards from scrimmage in a 24-7 Kansas City victory.So, if the Raiders (4-9) have any hope of knocking off the Chiefs (10-3) Sunday at O.co Coliseum, the defense is going to have to shut down Charles and force the Chiefs to go to the air.Yet the Raiders defense – after a strong start this season – has begun to come apart. With key injuries and a thinner crew, the defense has allowed 287 yards rushing over the past two games. That's an average of 143.5 per game, after holding opponents to 99.1 yards per game over the first 11 games.And, in losing three straight games, the...