KANSAS CITY, Mo. (AP) It seems that nobody is quite certain of the etymology of the term ''red zone,'' though many give credit to former Redskins coach Joe Gibbs for coining the term for the area inside an opponent's 20-yard line.
The Chiefs probably have their own choice words for it.
Many of them unsuitable for print.
For all the warts that dot their inconsistent offense, their baffling inability to score touchdowns when they get into the red zone may be the ugliest. And it is even more pronounced when stacked up next to Tennessee, which visits Arrowhead Stadium on Sunday, and just happens to be one of the best teams in the league at converting those opportunities into seven points.
Everyone from Chiefs coach Andy Reid to quarterback Alex Smith has tried to pinpoint the trouble, and they generally agree that it's a combination of play-calling, execution and simple unluckiness.
''We've been very good in the red zone at times, too,'' Reid insisted, almost as if he was trying to convince himself along with everyone else. ''They're all different. Everything is different down there, from the defenses that are played to each situation where you haven't had success.
''So you go back and evaluate it,'' Reid said, ''and you come back again and give it your best shot.''
There are inherent difficulties in scoring touchdowns in the red zone.
For one thing, everything gets compressed inside the 20. The field can't be stretched vertically, and that makes it easier to cover pass routes underneath, or stack up the line of scrimmage against the run.
Defenses also tend to sharpen their focus, knowing their backs are against the wall. Or at least the goal line. And that makes everything from blocking to catching require just a bit more precision.
''Everything has to be on point,'' Reid said, ''and it's got to be a little faster in there. We need to do a better job there, and I need to do a better job of putting guys in position.''
The Chiefs are scoring touchdowns on just 46.3 percent of trips inside the 20, which is tied for 27th in the NFL. By comparison, the Titans lead the league with a 71.4 percent conversion rate.
While Reid seemingly has been trying in vain to find the source of the Chiefs' red-zone ills, Titans coach Mike Mularkey knows exactly where to give credit for Tennessee's success.
''I think it starts with Marcus,'' Mularkey said, referring to second-year quarterback Marcus Mariota, who has thrown 32 touchdown passes without a red-zone interception in his career.
''I think a lot of it is because of his thought process, how quickly he thinks down there,'' Mularkey continued. ''He has a very quick release and there's not a lot of room for error down there, a lot of tight windows, and I think he's been very good with that.''
Mularkey also credited offensive coordinator Terry Robiskie and his other assistants for dreaming up a set of plays that always seem to work in those high-pressure, razor-thin confines.
''They've taken a lot of time and spent a lot of energy on those areas,'' he said.
Now, it would be foolish to think the Chiefs don't put similar emphasis on those scoring situations, especially given their struggles early in the season. During one two-week stretch, which included a brutal 19-17 loss to Tampa Bay, they managed just one touchdown on five trips inside the 20.
The low point may have come when Smith tossed an interception in the end zone against the Buccaneers, and Jameis Winston and Co. marched the length of the field for a touchdown that sealed the outcome.
''Especially down the stretch, I think those things only become more magnified,'' Smith said. ''They become more important as the games get bigger and bigger. No question.''
Hard for games to get any bigger these days.
The Chiefs are 10-3 and tied atop the AFC West with Oakland, but have the tiebreaker thanks to their two wins over the Raiders. Winning out would ensure Kansas City a first-round bye in the playoffs, and at least some level of homefield advantage for the playoffs.
''You know, it's always tough though too this late in the season with the work week and stuff,'' Smith said. ''You only get so many opportunities. Obviously, you're trying to take care of guys' bodies and get guys back out there, but no question. It's a huge priority.''
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