Steelers silence the Chiefs, 18-16, to advance to the AFC championship

His profession requires him to avoid distraction at all costs, so Chris Boswell unloaded his cargo with care, placing his white Beats by Dre headphones atop a pyramid created by his gym bag and backpack, before he noticed the crowd ahead of him. Inside a cramped cubbyhole in the lower confines of Arrowhead Stadium, a huddle of cameras awaited.

“Oh, wow,” Boswell groaned.

A fourth member of the Pittsburgh Steelers’ Killer B’s he is not. Compared to the vaunted trio of quarterback Ben Roethlisberger, running back Le’Veon Bell and wide receiver Antonio Brown, a kicker like Boswell cuts an anonymous figure. But he proved essential in an 18-16 victory Sunday over Kansas City, connecting on an NFL playoff-record six field goals as his team advanced to face New England in the AFC championship game next weekend in Foxborough, Mass.

“If he had one missed kick,” Bell said, “it’s a totally different game.”

Despite the misty, frigid, more or less wretched conditions, Boswell did not miss, and the Steelers did not suffer for the inefficiency of their scoring drives. Bell set a franchise playoff record with 170 rushing yards. Roethlisberger secured the victory just after the two-minute warning, connecting with Brown on a rollout to prevent the Chiefs from reclaiming possession.

As the Steelers savored the result, members of the Chiefs carped about the officiating. Bottled up for most of the night, Kansas City trudged through a 13-play, 75-yard touchdown drive to cut the Steelers’ lead to two with 2 minutes 43 seconds on the clock. But a holding call on tackle Eric Fisher negated a two-point conversion, and Pittsburgh safety Sean Davis broke up the next attempt.

It was a fitting denouement for a Chiefs team marred by self-inflicted wounds: six penalties, two turnovers and multiple drops. The penalty on Fisher infuriated Travis Kelce, Kansas City’s outspoken tight end. He suggested the official who made the call “shouldn’t ever be able to wear a zebra jersey ever again,” and ruled out one of the few other places of business that require such a uniform: “He shouldn’t even be able to work at Foot Locker.”

The rage obscured a night of subtle dominance by Pittsburgh. The Steelers controlled the football for 34 minutes. They punted once. Bell gashed his opponents. The only trouble was finishing drives.

“That’s not comfortable,” Steelers Coach Mike Tomlin said. “We desire to score touchdowns.”

It is an admirable goal, one that appeared within reach at the outset. After Boswell capped Pittsburgh’s opening drive with a 22-yarder, Kansas City answered with a five-play scamper down the field. Using Tyreek Hill as a weapon and a decoy, the Chiefs scored on a short throw to wide receiver Albert Wilson.

Pittsburgh regrouped and solved Kansas City’s brand of gimmickry. The next six Chiefs drives ended without points. Alex Smith often looked flustered in the pocket. Kansas City managed only 61 yards on the ground. Hill never gained more than nine yards on his seven touches.

As the Chiefs sputtered, the Steelers charged forward. Roethlisberger hooked up with Brown for a 52-yard bomb to set up the second field goal. Bell surpassed 100 yards in the second quarter. He moves in fits and starts, the product of his slippery, hesitation-heavy style, but his production was undeniable.

Willing to bend, the Kansas City defense proved difficult to break. That placed an extra burden on Boswell, who was kicking in less than ideal conditions.

Freezing rain had swept across the plains over the weekend, persuading the NFL to push the kickoff from afternoon to evening. The rain continued through the night. Fog descended as the hours passed.

Boswell did not appear to mind. Pittsburgh is not known for cheery winters, so “we’re used to it,” Boswell said. His longest attempt was 45 yards, but he also drilled a pair of 43-yarders. He limited his focus to setting his target with precision and striking the ball properly. It sounds simple, yet the weight of his lonely task is well documented.

Tomlin offered measured praise for his kicker’s performance. This was the effort the team expected, and consistent with Boswell’s performance since he joined the organization last year. His journey was peripatetic, typical for his profession: on the practice squad for Houston in 2014, cut by the Giants in 2015, a vital member of a playoff team in 2016.

His fourth field goal gave the Steelers a five-point lead heading into the half. The fifth and sixth held the Chiefs at bay. After the defense stopped that last two-point conversion, the lead fell into the hands of Bell, Roethlisberger and Brown.

“It’s not just me out there,” Boswell said. “All three phases played well tonight. I was just happy that special teams had a really good night.”

andy.mccullough@latimes.com

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