The clock was ticking down with six second to go. The Bengals' defense was on the field after the offense had just scored a field goal to tie up the game, 31-31. The Bengals had the momentum, though the Cardinals were decisively driving down the field after the game-tying field goal. And then, after a game riddled with penalty flags, another one landed on the field.
Bengals' defensive tackle Domata Peko was flagged for unsportsmanlike conduct due to the official believing he was simulating a snap call. As that happened, Cardinals offensive linemen began to move, making the rest of the Bengals' defense believe the penalty was on them.
Instead, it was a very rare penalty call on the Bengals that led to a 15 yard penalty and a chip shot from the Cardinals to win the game, leaving two seconds left on the clock.
Peko has his own side of the story as to what happened, per ESPN. "We were still running back from our prior play, and I was just saying, 'Get set, get set, get set,'" Peko said. "I don't know if 'set' sounds like 'hike' to them. I don't know if it was the way I said it quicker like, 'Get set!' with the bass in my voice or whatever. I don't know."
Marvin Lewis also doesn't believing the flag was warranted. Per Bengals.com:
Head coach Marvin Lewis said he believed his player and was surprised the call was made, calling it "a phantom play." Cards right guard Ted Larson said Peko had been doing it all game.
"I trust what our player did and said. He’s alerting a run and not anything to do with what they’re saying," Lewis said. "I don’t see how they make that call at that point in the game like that. I trust our guy to be honest with me."
As you'd expect, Cardinals quarterback Carson Palmer doesn't buy into that side of the story. Per Coley Harvey, "It was real obvious," Cardinals quarterback Carson Palmer said of Peko's penalty. "The ref was right there. They obviously said the snap count, and that's a 15-yarder."
Had the penalty been against the Cardinals and not the Bengals, the game would have gone to overtime due to the NFL’s 10-second-runoff rule. Per the MMQB:
When there’s a dead-ball penalty at this time of game against the offense, 10 seconds are run off the clock automatically unless the offense chooses to use a timeout; the Cardinals had no timeouts left.
Instead of going to overtime, the game instead ended in crushing and dramatic fashion. Whatever happened on that play doesn't matter now, but regaining some discipline after a night that saw the Bengals have 10 penalties for 108 yards is something that needs to be addressed.