Bruce Arians's risky but brilliant playcall sealed the deal late in the game for the Cardinals against the Seahawks, as Andre Ellington scored the touchdown that secured the Cardinals of a crucial victory over their division rivals.

SEATTLE —When I spoke with Cardinals head coach Bruce Arians this week about his offensive philosophies, he revealed the primary root of the structure: use base plays out of unconventional formations, and surprise the defense you're playing, game after game.

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“I don’t think there’s any doubt,” he said, when I asked about the idea that an offense that's easy to discern is easy to defend. “Two things: you have to be able to run the ball and stay two-dimensional, but you also want to be able to have enough things in your offense this week that they didn’t practice on Wednesday and Thursday.”

In the play that socked away Arizona's 39–32 win over the Seahawks at CenturyLink field on Sunday night, Arians's team did both of those things. With 1:58 left in the game, Arizona lined up with three receivers to the right and an iso receiver to the left side, and ran Andre Ellington to the single-receiver side. Most coaches would have forced the call to the dominant receiver side, but Arians knew that Seattle's defense would angle that way, and if he caught the defense just right, Ellington would have a free lane.

That's exactly what happened, and Ellington cruised 48 yards for a touchdown, putting Arizona up, 39–29.

The Seahawks had scored two defensive touchdowns on Carson Palmer fumbles in the fourth quarter, and had all the momentum on their side at that point. It took a ballsy playcall to turn that back around, and when it comes to that aspect of the game, few coaches are as courageous as Arians. Arizona's backup quarterback Drew Stanton showed us all just how exciting it was for the Cardinals that the play was pulled off successfully by doing a completely preposterous and entertaining dance on the sideline as Ellington ran away with the game.

Stanton later told me where that reaction came from, and he also mentioned a bit of a method behind Arians's madness.

“My heart,” Stanton said of the dance with a laugh. “It came from my heart.”

“No, seriously,” Palmer chimed in from the cubicle next to Stanton's in the visitors' locker room. ”It came from his heart.”

“It was raw emotion,” Stanton continued. “Just excited—that was a risky play call that was very beneficial for us.”

I asked about Arians's play-calling courage, and Stanton, who was with Arians with the Colts a few years back, revealed that it wasn't the first time he'd seen this particular play.

“That's what I was telling all those guys [his teammates] as soon as he called it—we were in Indianapolis on a third-and-11 in Kansas City, Week 16, to clinch a playoff spot for us. Similar situation where we needed a first down, they were pinning their ears back rushing, and we put that play call in for a great play.”

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​Arians's concepts have commonalities and precedents, but no coach is better at taking base formations and throwing new wrinkles in the pot. That's how he kept Seattle's defense off balance just enough, as furiously as that defense played. Palmer completed 29 of 48 passes for 363 yards, three touchdowns and one interception, but he was also pressured ceaselessly, especially when Seattle went against type and blitzed more heavily than expected. Just as that pressure hindered Palmer's attempts through most of the game, it also opened things up for that Ellington touchdown.

“We liked that play,” Arians said after the game. “We ran it earlier with a bubble screen instead, and at that point in time, we were going to try to get their last time out and punt it down there. But we really liked the play, and Andre just hit it perfectly against the blitz. A lot of people were saying, ‘Get out of bounds,’ and I'm saying, ‘Stay in bounds. Go score. S***.’”

Seahawks coach Pete Carroll saw it from an atypical angle. He was suddenly watching as a man whose defense was fooled, an event that doesn't happen all that often.

“We went after them, and they ran a draw, where we could have run right into it and killed it. We didn't They got through, it was a nice job by them, and I don't know how we got pinned inside the sidelines like that. We always defend the sidelines and get the ball to turn back. I think we were surprised, maybe, I don't know.”

It was one play, but it was also emblematic of a Cardinals team that knows what could have been, and is now desperately trying to make the most out of the opportunities in front of it. Last season, of course, the Cardinals were 8–1 when Palmer went down for the rest of the 2014 campaign with a knee injury, and finished the regular season 11–5 with Stanton and Ryan Lindley as the backups. Two of those games without Palmer came against the Seahawks, and those two losses decided the NFC West in Seattle's favor. Now, at 7–2 and three games ahead of their nemesis (who now sits at 4–5), there's a different feeling because Palmer is on the field and locked in. He is unshakeable even in the face of defensive pressure and the mistakes it can bring.

“It's huge,” Arians said. “Everyone's talking about how we haven't played anyone yet, and I think we played someone pretty good and handled ourselves extremely well. This is not an easy place to play, and like I've said, I wanted to come back here with Carson. I'll come in here with Carson any day of the week.”

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As for the Seahawks, coming back from a 19–0 second-quarter deficit was impressive, but the same problems that have plagued this team all year showed up at the worst possible times. The two-time defending NFC champs came into the 2015 season with a new offensive line and a new philosophy—that they could take collegiate defensive linemen, exploit their athleticism, and somehow avoid the inevitable issue common to all great lines—blocking in tandem requires time and communication. Assistant head coach Tom Cable sold Carroll a bill of goods, and the result has been the league's worst offensive line this season. Russell Wilson was running for his life most of the night, which was complicated by the fact that that line was racking up penalties at a ridiculous rate. The Seahawks finished the game with 14 penalties for 131 yards, and while it's true that Clete Blakeman's crew was overwhelmed—blowing more than one obvious call on each side of the ball—this was more about a sloppy Seahawks team that must now hope for luck to maintain any hope of a return to the postseason.

“Those guys are kind of in our way,” Arizona defensive back Tyrann Mathieu said this week of the Seahawks. “We want to go somewhere, and we have to go through those guys.”

After the game, Mathieu expanded on that thought.

“It was important for us. We got a good lead on those guys, they came back, and they made some plays. I think the key thing for us was that it wasn't one of those things in the past, where we let those guys keep scoring touchdowns. We were able to put a stop to it. When they made their plays, we came back and made our plays. It was a great confidence-builder for us.”

‘Going through those guys’ was easier than it's been before, and maybe this is the year Arians's team can take their momentum all the way.

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If that's the case, it's not just Arians and Palmer who will decide it. Arizona's defense, one of the best and most opportunistic in the NFL this year, kept Wilson on his toes when it wasn't throwing him to the ground. Mathieu had an interception, Wilson completed just 14 passes in 32 attempts for 240 yards, and Seattle's formerly peerless rushing attack was relatively silenced.

This reversal of fortune is due in part to Seattle's mistaken identity in 2015, but it has just as much or more to do with the fact that Arians's team has found its pulse, and its courage, and its confidence. The heroes are aligned, and the strategies are working.

Even the ones so outlandish, they make backup quarterbacks do loony dances on the sideline.