It was the signature moment from a signature performance.
Late in the second quarter, against the most talented offense that they've faced this season, the Patriots were able to stop the Steelers from getting to the end zone despite giving Ben Roethlisberger and his teammates a first-and-goal situation from about six inches away.
Limited to a field goal, the Steelers were only able to reduce the Patriots' lead to 17-9, and the hosts went into halftime with all the momentum.
How did Bill Belichick and Matt Patricia's defense do it? Here's how Patriots players saw it break down, starting with the play that put the Steelers on the doorstep of the end zone.
3rd-and-8 at PATRIOTS 19, 2:00
From the shotgun, Roethlisberger found tight end Jesse James one-on-one with safety Patrick Chung. James caught the out-route at the 6-yard line and then dragged Chung toward the pylon. Combined with Duron Harmon, who broke on the ball as soon as it was thrown, the pair combined for the tackle.
The play was ruled a touchdown, but it was changed upon review.
"I gave up that pass and Du came in," Chung said. "He came and finished him off a little bit to keep him from getting in. We got bailed out on that one. Du bailed us out on that one."
"We always talk about just swarming to the ball," Harmon said. "Never leaving a man out to dry. And I just wanted to get over there as fast as I can, just to give them some help, just to make sure he didn't get across the line."
"That was huge," Devin McCourty explained. "I told [Harmon] as soon as he got in the sideline that was a big tackle, from Chung hustling and then [Harmon] making sure he didn’t get across the goal line. That gave us a shot and that’s how we play defensively. It’s all about the next play. It’s about everybody fighting hard to finish."
1st-and-GOAL at PATRIOTS 1, 1:53
"You got to make a play," Chung said, relaying the feeling in the defensive huddle after the review. "Hold them to three points. Got to make a play. Just don't let them in the end zone. That's pretty much what the conversation is. And go from there, bro. Bend but don't break."
"It's time to go," said rookie Vincent Valentine." This is the most important part of the field. The coaches harp on this every day. Just keeping them out of the end zone. That's what we're going to try to do every time. And we're going to boost the intensity level up even more."
The Steelers wanted to hammer home a score on first down, deploying four tight ends, and motioning two to get three on the left side of the formation.
When Roethlisberger handed off to DeAngelo Williams, the play was designed to follow the formation's strength, but Chung was unaccounted for off of the right edge.
"I just read my keys," Chung said. "Run play."
Pittsburgh's right tackle blocked down and, with no tight ends on his side to slow him down, Chung was unimpeded to Williams. It appeared as though Williams stutter-stepped as he got to the line, seeing some penetration from Alan Branch. That may have been just enough hesitation to allow Chung to close.
The Patriots had survived first down, and they'd pushed the Steelers back a yard. They had a chance, thanks to Harmon's help in tackling James.
"It shows the importance of people not giving up on plays and always running to the ball," Chung said, reflecting back. "That's what we're coached."
2nd-and-GOAL at PATRIOTS 2, 1:50
The Steelers went with four tight ends on second down as well, using a balanced line this time. The hand-off went to Williams, and though the edges were blocked this time, the middle was not.
Right guard David DeCastro pulled, seeking out linebacker Dont'a Hightower. In DeCastro's absence, right tackle Marcus Gilbert tried to split the difference on Valentine and Branch. He whiffed on both, and Valentine happened to be the first to the ball.
"I don't know what was happening that play, but I made the play," said Valentine, who tripped but caught himself as he burst into the backfield. "That's all that really matters. I stumbled a little bit. I guess I kind of crossed over my feet a little bit, but I ended up making up for it.
"I was really surprised. I got in there and I didn't know where the back was. I looked up and he was right there."
3rd-and-GOAL at PATRIOTS 5, 1:47
The Steelers were now backed up to their 5-yard line and opted to spread things out.
They motioned slot receiver Eli Rogers to the right side of the formation, giving them a bunch on the right with Antonio Brown as the lone receiver on the left.
When Rogers motioned, corner Logan Ryan followed him. And as Ryan moved closer to fellow corner Eric Rowe, the two exchanged a brief hand signal.
"On that last pass play, it really came to film study," Rowe said. "When they motion over to that bunch, me and Logan we were going to combo it."
Rowe added: "Nothing verbal. We just have a little signal out. Just real slight. You don't want to make it too obvious because then the receivers know, the quarterback knows, and then maybe they change. We just do a real slight signal where they can't catch it and then play the play from there."
Rowe and Ryan had decided that they would switch if the Steelers tried to run a pick play. That meant Ryan would take Cobi Hamilton if Hamilton ran a crossing route, and Rowe would take Rogers on an outward-breaking route.
That's exactly what the Steelers tried to do, and the Patriots cover men were prepared. Perhaps sensing pressure from Jabaal Sheard, Roethlisberger threw quickly and out of Rogers' reach.
"They tried to do a pick out on Logan. They knew that he was guarding [Rogers]," Rowe said. "And I was like, 'This is going to fall right into my lap.' I think someone pressured him because [Roethlisberger] got it out quick. I was like, 'Oh if he gets it, I'm going to smack him.' But he threw it too far ahead so we'll take that, too."
"We’ve seen multiple times games," coach Bill Belichick said, "or in some cases seasons, come down to a yard, and so that was a big yard there at the end of the half. The tackle, and then the first-down goal-line play was stopped. Valentine got the second one, and then we were able to get a stop there on third-down, so that was a big-four point swing."
"That's a big lift," Rowe said. "They're a great team and a great offense. To make a stand like that from the two or three-yard line? That just gives the whole team confidence. Even if they get a field goal that gives the whole team confidence just to let people know that we are a tough team."
A tough team. A team that hasn't broken despite moments when it has bent. It's an identity that they take pride in.
"I kind of like it," Harmon said of the bend-don't-break description that has followed this unit. "It just shows the type of toughness and mental toughness we have. Even when the situation might seem terrible or might seem bad, we have enough mental toughness to come out and make a positive out of it."