They're still in position to do it. But how they've reached that point is nearly unprecedented.
After beating the Texans that September day, the Chiefs proceeded to lose five straight, along with star running back Jamaal Charles to a season-ending injury. They lost to division rival Denver on a fumble returned for a touchdown and to Chicago on a last-minute TD toss, their season so full of expectations spiraling perilously out of control.
Things weren't a whole lot better in Houston, where star running back Arian Foster was lost to his own season-ending injury. There was a quarterback controversy, lousy play by a historically solid defense and very little reason to think that things would turn around.
Yet they have. For both teams.
''I have tremendous respect for this football team,'' Texans coach Bill O'Brien said. ''We've made some changes to the scheme and personnel-wise, and things like that, but I think overall these guys, there was never a time where I questioned any of their work ethic ever.
''They put a lot of time in,'' he said. ''They care about winning. They care about each other.''
There is no blueprint for digging out of the cellar, no trusted formula for turning around a season in disrepair. Most of the time, the kind of start the Chiefs (7-5) and Texans (6-6) got off to this season would have fans thinking about next season, or at the very least the NFL draft.
You know, where they would probably be picking early.
Beginning with the AFL-NFL merger in 1970 through last season, there were 197 teams that started 2-5 - the exact record Kansas City and Houston had seven games deep. Four managed to scratch their way into the playoffs, putting the odds of it happening at roughly 2 percent.
That's about the same probability of drawing three of a kind in five-card poker.
''You know, you never want to start a season the way we started,'' said Chiefs linebacker Derrick Johnson, an 11-year veteran who's spent his entire career in Kansas City. ''But I've been in this league long enough to know that winning in November and December gives you a chance.''
Ask a dozen players in either locker room what turned things around this season and chances are you'll get a dozen answers. Or at least, a dozen variations of the same worn cliche: They stayed together, never got down on themselves, played as a team.
The reality is much more complex.
There were changes to personnel - the Texans settled on Brian Hoyer at quarterback, the Chiefs on a trustworthy offensive line. There were tiny schematic tweaks, the kinds of changes that usually go unnoticed by all but the most hardened football eye. And then there was the schedule, which eased up for both teams after a rough stretch against fellow playoff contenders.
''Listen, we were playing really good football teams early in the year - not that we're not now - but we were playing good ones when you're just getting everything together with young players, with guys coming back off whatever situation they're coming back off,'' Chiefs coach Andy Reid said. ''But we've improved and the guys have stayed on task at doing what they need to do.''
Eventually, both teams won. Then one win became two, and two became a winning streak. Now, the Chiefs have won six straight while the Texans have won four of their last five.
''Winning can cure a whole lot of things,'' Texans star J.J. Watt said. ''Whether it's aches and pains that don't necessarily feel like aches and pains anymore. Whether it's just the overall attitude, confidence. Whether it's studying more. It's just a much better place when you win.''
And all that losing early on? It may turn out to be a blessing.
The Chiefs lead the wild-card standings heading into Sunday's game against San Diego, and the Texans are tied with Indianapolis in the AFC South as they prepare for New England. But while other teams may start looking at the big picture, at potential playoff implications, the Chiefs and Texans have overcome their lousy start by focusing solely on the game at hand.
''We realize why we're in this situation, because of the work we put in,'' Watt said. ''People can try and look at it like it was some sort of overnight switch from five weeks ago, but it's really been a day-to-day process to make this happen and it's going to continue to be a day-to-day process. We just come out here every day and we work hard to make sure that we continue this streak that we've been on. I think we're doing a great job of that.''
AP Sports Writer Kristie Rieken in Houston contributed to this report.
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