A two-year playoff absence is barely a hiccup in most NFL cities. In Pittsburgh, it's a drought that forced one of the league's most successful franchises to rebuild itself on the fly.

Consider the project right on schedule.

Ben Roethlisberger passed for 220 yards and a touchdown, Le'Veon Bell added a score and the Steelers locked up a postseason berth with a methodical 20-12 win over the Kansas City Chiefs on Sunday.

Pittsburgh (10-5) faces Cincinnati next week for the AFC North title. Either way, the Steelers will be playing January football for the first time since Tim Tebow and Denver stunned the defending AFC champions in the wild card round three years ago.

Now, Roethlisberger, Bell and Antonio Brown lead one of the NFL's best offenses, and the defense is starting to show some snarl for the only franchise with six Lombardi Trophies.

Alex Smith passed for a season-high 311 yards but was sacked six times as the fading Chiefs (8-7) lost for the fourth time in their last five games. Kansas City had little trouble moving the ball but couldn't seem to get the one big play that mattered.

Instead, the big plays — and most of the smaller ones — went to the Steelers. A roster that's undergone a youth movement since a Super Bowl appearance four years ago is growing up quickly, though with a few familiar faces leading the way.

The Steelers' win also eliminated the Dolphins from the playoffs. The Chiefs need to beat San Diego next Sunday and receive plenty of help to make it back to the playoffs for a second straight year under coach Andy Reid.

Roethlisberger wasn't as dynamic as he's been at times this season but led a pair of long touchdown drives. The second ended with a 3-yard strike to Brown that gave Pittsburgh a 17-6 lead late in the third quarter. Roethlisberger briefly went to the locker room with a right knee injury but returned after a Kansas City field goal to guide a 12-play, 70-yard march that ended with Shaun Suisham's 23-yard kick with 4:04 remaining to all but clinch it.

The teams spent the first half trading methodical drives, but Kansas City kept getting bogged down near the end zone, a rarity for a team that came in second in the league in red zone touchdown percentage. Three times the Chiefs drove inside the Pittsburgh 20. Three times they failed to cross the goal line.

The first drive ended with Cairo Santo's 23-yard field goal.

The second included a flip from holder Dustin Colquitt to tight end Travis Kelce on fourth-and-4 at the Pittsburgh 11. Kelce converted it into a first down, but three additional downs produced a single yard and another kick from Santos.

Pittsburgh responded to go in front 10-6 when Bell ended a crisp 80-yard drive with a 1-yard dive over right tackle. Smith deftly guided the Chiefs back downfield when a rare moment of aggression by Reid wound up costing Kansas City a chip-shot field goal.

Facing fourth-and-inches at the Pittsburgh 12 with 27 seconds left in the half and no timeouts, Reid sent the offense back onto the field. Charles was drilled by Lawrence Timmons behind the line of scrimmage, and when Will Allen piled on, the Steelers had the ball and the momentum with a postseason berth just 30 minutes away.