PITTSBURGH — The drive that put the NFL’s last unbeaten team on notice started three feet from the Pittsburgh Steelers own end zone.

Over the course of the next five minutes, the Steelers put their considerable offensive talents on display. They literally pushed the Kansas City Chiefs from one end of the field to the other, quieting the Arrowhead Stadium crowd one Ben Roethlisberger pass and Le’Veon Bell run at a time.

Then, six feet from a touchdown that could have blown things open, the $92 million offense went backward. Again. An incomplete pass, a 4-yard loss by Bell and another heave by Roethlisberger that fell to the turf later, Chris Boswell came out for a field goal that gave Pittsburgh a 12-3 lead the Steelers know should have been larger.

“We were all like, `What are we doing, why can’t we get this ball in?”’ guard David DeCastro said. “It’s frustrating. You drive all the way down there and all of a sudden you kick 3 points. You had all the momentum in the world and we just love making our life hard here. I don’t know what it is.”

Whatever it is, it’s keeping the pre-planned touchdown celebrations by Pittsburgh’s offensive stars largely under wraps. While the Steelers (4-2) held on to beat the Chiefs last Sunday, their struggles punching it in have allowed teams to stick around far longer than necessary.

Pittsburgh is tied for 16th when it comes to finishing red zone drives with touchdowns. The teams the Steelers are tied with in that category include the winless Browns and 49ers. The Steelers rolled up 432 yards in Kansas City and scored all of 19 points , something they know has to change starting this week against Cincinnati (2-3).

“We got all the way down the field a lot,” Bell said. “We just didn’t punch the ball in the end zone consistently. I think that’s what I want us to evolve to. We need to clean some things up. There’s little minor details that are killing us.”

Two weeks ago, the Steelers trailed Jacksonville by a point starting the second half. Pittsburgh slowly moved all the way to the Jaguars 5. Poised to take the lead and control, Roethlisberger sandwiched a 3-yard shovel pass to Bell around a pair of incompletions. Boswell’s field goal gave the Steelers a 9-7 lead, one that disappeared following a pair of pick-sixes thrown by Roethlisberger later in the quarter.

A touchdown on that drive and maybe the Steelers aren’t wondering how the Jaguars beat them by 21 points at home .

“As the field gets tight down there, the little small fine details coaching points become very critical because there’s very little margin for error,” offensive coordinator Todd Haley said. “There’s less margin for error down there so you need to be on point.”