It's a different Steelers' team than the one that lost to New England in late October, a different Steelers' defense.

Cameron Heyward understands and appreciates, perhaps as well as anyone, the transformation undergone by the Steelers' defense since their 35-30 loss to Dallas on Nov. 13 at Heinz Field.

"I was the sacrificial lamb," Heyward maintained.

Heyward played his last snap at defensive end against Dallas before winding up on the Reserve/Injured list on Nov. 19 with a pectoral injury.

The Steelers' defense emerged from that gut-wrenching loss to the Cowboys ranked No. 25 in total defense, No. 15 against the run and No. 25 against the pass, and having failed to hold a 30-29 lead for the final 42 seconds.

Running back Ezekiel Elliott crossed the goal line on his game-winning, 32-yard touchdown run with nine seconds remaining.

The Steelers' overall record dropped to 4-5.

But rather than despair, they dug in.  

"You beat the drum hard enough, you're either going to break it or it's going to work and make some noise," Heyward maintained. "All the things we preached about we continued to preach about. I don't think anyone thought we were beating a dead horse. It finally got instilled and you reap the benefits from it.

"It wasn't on life support, but we know what we needed to do. Losing a heartbreaker like that, we put ourselves in a situation where it wasn't perfect. But week in and week out you see guys stepping up. You just appreciate what they're doing."

What they're doing now is getting in and staying in the right gaps.

And tackling, and making plays individually when plays come their way.

They've stopped trying to do too much, stopped trying to do more than their individual assignments require.

They also haven't lost since losing to the Cowboys.

What the Steelers' defense did between Dallas and the conclusion of the regular season was enough to improve to 12th in total defense, 13th against the run and 16th against the pass.

And in two playoff games, the Steelers' defense has held opponents to averages that include 266 total net yards, 56.5 rushing yards and a 34.8-percent success rate on third-down conversions. The Steelers are averaging one fumble recovery, one-and-a-half interceptions and three sacks per playoff game.

Heyward has remained in the thick of it all, in the locker room and at practice, on the road trips and on the sidelines, observing, coaching, inspiring and otherwise doing whatever he can to lend a hand.

"We've seen a lot of guys who are younger who have completely done a 180 and have grown a lot," he said. "(Cornerback) Stephon Tuitt, a guy who had a year (with the Steelers) under his belt (prior to this season) is totally confident in what he's doing. He's comfortable in the role he's in.

"You have guys like (rookie cornerback) Artie Burns and (rookie strong safety) Sean Davis, and my favorite, 'J-Wobble' (rookie defensive tackle Javon Hargrave), guys like that who were getting thrown into the fire early and are making big strides.

"And then you get guys who were injured like (second-year outside linebacker) Bud Dupree that come back and have a sudden spark. You combine it all together and you're gonna have some guys who are stepping up."

The defense has stepped up enough to help get the Steelers to within one step of the Super Bowl.

Only the Patriots stand in the Steelers' way.

"We gotta have a good gameplan and I think we do," Heyward said, looking ahead to Sunday.  "We gotta stop the run, stop the easy passes to the running backs and then we gotta win the turnover battle. We've done that throughout this run we've been on.

"It can't be anything different."