For N.F.L., Curious Results Set Up a Wild Final Weekend

A day after Baltimore muffled the Chargers, becoming the first team to hold them below 20 points, Seattle held the ball for more than 35 minutes against Kansas City. Though the Chiefs trailed by only 4 points at halftime, they ran the ball only five times in the second half, and three of those rushes were scrambles by Mahomes.

“I don’t know that we’ve played any more complete than we did in a game when we needed it, against such a good team,” Seahawks Coach Pete Carroll said. “That was a blast. That was just so much fun, the whole thing was.”

Not for the Chiefs, of course. They scored on four of five second-half possessions. The Seahawks countered with touchdowns immediately after three of them, then ran out the clock on the fourth. After Sunday, Kansas City ranks 30th in the N.F.L. in points allowed.

According to research conducted last playoffs by the sports data service Sportradar, no team since 2000 ranked that low has reached a conference championship game, let alone the Super Bowl. The closest analogue was the 2008 Arizona Cardinals, who were 28th in points allowed.

Only Kansas City has scored more points than New Orleans. And yet, across the last three games before Sunday, when the Saints’ offense produced only 50 points, they managed to go 2-1 — losing by 13-10 at Dallas — because of a defense that, according to Pro Football Reference, allowed the fourth-fewest yards and the third-fewest points in the league over that span.

That same defense allowed 380 passing yards to Ben Roethlisberger, 300 of which went to Antonio Brown and JuJu Smith-Schuster. But it also forced two fumbles in the fourth quarter, including Smith-Schuster’s at the Saints’ 35-yard line in the final minute, and had the awareness to stop Roosevelt Nix a yard short of a first down on an audacious fake punt with about 6 minutes left.

“We’re playing as a team right now,” Saints cornerback Marshon Lattimore told reporters. “At the beginning of the season, it was all offense. Now, we are playing hard as a defense. I can’t wait for the playoffs.”