NFL playoff picture should soon become clear

As the NFL’s regular season nears an end, with 15 weeks of more parity than clarity in the books, the playoff picture is starting to come into focus.

Three teams can clinch division crowns by winning Sunday: Atlanta, Philadelphia and New England.

Four more teams can lock up postseason spots by winning: New Orleans, Baltimore, the New York Giants and the New York Jets.

Kansas City, which plays host to Tennessee on Sunday, needs a win and a loss by San Diego (at Cincinnati) to claim the AFC West a week early.

The Chiefs pulled off a big win under pressure Sunday when, after a blowout loss in San Diego, they responded with a 27-13 victory at St. Louis to maintain control of their destiny in the division.

Coach Todd Haley said his team’s “sense of urgency was terrific” with its performance against the Rams. The Chiefs (9-5) now finish with two games at home, where they have not lost this season.

Twenty teams are still in contention to make the playoffs, even though many of those would burn out their calculators trying to determine how they would get in.

Only four teams can exhale even slightly, knowing they’re in the playoffs but haven’t secured the seeding they want — the Patriots and Pittsburgh Steelers in the AFC, and the Falcons and Chicago Bears in the NFC.

“We’re not slacking off just because we are in the playoffs,” Falcons defensive end John Abraham told the Atlanta Journal-Constitution. “We still have goals to reach.”

Some of the Week 16 games to watch …

New Orleans at Atlanta: Like the Patriots, the Falcons have proven to be especially tough at home. They are 19-1 at the Georgia Dome with Matt Ryan starting at quarterback. When the Falcons and Saints met in Week 3 at the Superdome, Atlanta won in overtime, 27-24.

New York Jets at Chicago: The Bears have clinched their division, but still have the big incentive of a first-round bye within reach. The Jets are hoping Mark Sanchez picks up where he left off in a victory at Pittsburgh, although they’re concerned about his sore right shoulder.

San Francisco at St. Louis: Even at 5-9, the 49ers have a chance to end their seven-year playoff drought. So far, Coach Mike Singletary isn’t saying who will start at quarterback — but we know that player’s last name will be Smith. It’s either Alex or Troy.

N.Y. Giants at Green Bay: Many had considered the Packers to be one of the Super Bowl favorites before they were hit with a slew of injuries, the latest to quarterback Aaron Rodgers (concussion). Rodgers has not been cleared to return yet, but this much is clear — if Green Bay loses, it is eliminated from playoff contention. If the Giants win, they clinch a playoff spot.

sam.farmer@latimes.com

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