Le'Veon Bell ran for 179 yards and a touchdown, Antonio Brown made an acrobatic touchdown catch in the fourth quarter and the Pittsburgh Steelers held on to beat the Kansas City Chiefs 19-13 on Sunday.
The Chiefs (5-1) still had a chance after Brown's 51-yard reception made it 19-10, moving quickly down the field and getting a 33-yard field goal from Harrison Butker.
And when their defence forced a quick three-and-out, Tyreek Hill's 32-yard punt return gave them the ball with 1:48 to go.
But after the Steelers (4-2) gave up a first down, James Harrison sacked Alex Smith on third-and-10, and the quarterback's incomplete pass on fourth down left the NFL with no unbeaten teams.
Ben Roethlisberger was 17 of 25 for 252 yards for Pittsburgh, bouncing back from his abysmal five-interception performance against Jacksonville last week.
The game in many ways resembled January's divisional playoff game at Arrowhead Stadium, when Bell churned for 170 yards rushing and the Steelers' defence shut down the Chiefs in an 18-16 victory.
Their defensive dominance was even more impressive considering the circumstances: The Steelers had allowed more than 200 yards rushing twice in the past three weeks, while Kareem Hunt ran for 107 yards and the Chiefs piled up 450 yards in a shootout victory last Sunday in Houston.
Kansas City rolled into the game averaging 414.2 yards and 32.8 points, but the Steelers shut down NFL rushing leader Hunt, who gained just 21 yards on nine carries. They also spent the afternoon with their paws on Smith's jersey, holding the league's top-rated passer to 246 yards and a touchdown.
Still, Smith nearly rallied the Chiefs in the second half, hitting De'Anthony Thomas down the sideline for a 57-yard fourth-quarter touchdown that got Kansas City within 12-10.
But the Steelers answered with Bell, whose hard running got them near midfield. And when they faced third-and-2, former Chiefs coach and Steelers offensive co-ordinator Todd Haley dialed up a pass down the sideline to Brown, who caught the tipped ball and ran it 51 yards for the score.
It was Brown's 52nd touchdown reception, passing Lynn Swann for third-most in franchise history.