Three plays went backward a dozen yards and Greg Zuerlein missed a 38-yard field goal.
Nothing went right for the Rams the rest of the afternoon.
Charles rebounded to finish with two touchdown runs, Knile Davis returned a kickoff 99 yards for another score and the Chiefs rolled to a 34-7 victory, their sixth straight in the series dating to Sept. 24, 1994, when the Rams were still based in Los Angeles.
''We just made some mistakes and didn't take advantage of some opportunities,'' said Rams tight end Lance Kendricks, who had their lone touchdown. ''A fumble recovery in the red zone, we have to score a touchdown there. There's no excuse for that.''
Cairo Santos promptly kicked the first of his two field goals, a career-best 53-yarder, and the Chiefs were off and running. Davis added his kick return TD to start the second half, and he capped a run of 34 straight points with his short touchdown run late in the game.
Alex Smith finished 24 of 28 for 226 yards passing for Kansas City (4-3).
''Any time you play good in all three facets, you're going to win a lot of games, and it felt like we did that,'' Smith said. ''Early on offensively we left a little bit out there, kind of let them off the hook a bit, but they're a good defense. There in the second half we got rolling.''
''They took some things away and when that happens you've got to find a way to get some momentum offensively,'' Austin Davis said, ''and we weren't able to do that. But my hat really goes off to them. They did a really good job and made a lot of good plays.''
In a game dominated by Kansas City, here are a few things that stood out:
INJURIES HURT: The Rams lost left tackle Jake Long to a knee injury, right guard Rodger Saffold to a shoulder injury and wide receiver Brian Quick to an arm injury. Defensive back Rodney McLeod and center Scott Wells also missed time. Coach Jeff Fisher did not know the extent of any of the injuries, but it appeared that the injury to Long may have been the most serious. ''I'll assess our injury situation in the next 24 hours,'' Fisher said. ''I know we're going to have some players miss some time. How much and whom, I don't know.''
SACK ATTACK: Houston has 10 sacks this season, halfway to the franchise record of 20 set by Derrick Thomas. Houston had 11 last season before missing five games due to injury. ''I just focus on what I can do,'' he said. ''I just get the call from the coaches and zone in.''
SICK KICKER: Zuerlein has been dealing with an illness this week, though Fisher refused to say that had anything to do with his botched field goal. Zuerlein also struggled on kickoffs.
GOVERNOR'S CUP: The Chiefs were awarded the silver trophy as the winner of the cross-state rivalry by Missouri Gov. Jay Nixon. The Rams have never beaten the Chiefs in the regular season since moving to St. Louis, but they had owned the trophy by virtue of a 2012 preseason win.
KNILE OR NEVER: Davis, who had a history of fumble troubles in college, has now proven to be a dependable kick returner. His return Sunday was the second TD of his career. ''This whole season we have been one or two blocks from getting it in the end zone,'' he said. ''Right before we took it out, Coach was like, `Man, we're overdue for one.' We ended up busting one, so that was pretty neat.''
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