NEW ORLEANS — From his position in the right slot, Los Angeles Rams cornerback Nickell Robey-Coleman scanned the New Orleans Saints’ formation. It was third and 10 on the Rams' 13-yard line with less than two minutes left in a tie game. He knew the Saints were in 11 personnel — one running back, one tight end — but saw Saints running back Alvin Kamara lined up across from him. The Saints had broken the huddle quickly, so he anticipated a sudden snap.

“Hold on,” Robey-Coleman thought. “Something ain’t right.”

Robey-Coleman’s instincts led to the decisive play of the Rams’ 26-23 overtime victory in Sunday’s NFC championship game in the Superdome, a brilliant maneuver concealed by controversy. Robey-Coleman would commit a blatant pass-interference penalty, tackling wide receiver Tommylee Lewis before quarterback Drew Brees’s pass arrived, only for officials not to throw a flag. Rather than draining the clock and kicking a game-winning field goal, the Saints went up three, gave the ball back to the Rams and lost in overtime.

In the postgame locker room, Robey-Coleman had still not seen the play. He promised an honest answer if a reporter showed it to him. Upon viewing the play, Robey-Coleman burst out laughing.

“Oh, hell yeah,” Robey-Coleman said. “That was P.I.”

Robey-Coleman was willing to take the pass-interference penalty to prevent a touchdown, but he received a surprising bonus when officials held their flags. Yet Robey-Coleman’s pass interference was not the brilliant part of the play. The brilliant part of the play was being in position to commit pass interference.

On replays, it looks like Lewis burned Robey-Coleman. Those replays, according to Robey-Coleman, are lies.

“If they look at the whole play, they would have known that wasn’t even my dude,” Robey-Coleman said. “Kamara was my dude.”

Robey-Coleman ended the play on the defensive left sideline, but he had started on the right side of the formation, lined up across from Kamara in the slot. He knew the Saints' other running back, Mark Ingram, was not in the game, and he knew the Saints’ personnel package included only one running back. Because Kamara was in the slot, there was a wide receiver in the backfield.

Robey-Coleman didn’t see Lewis at first because the 5-foot-7, 160-pound wide receiver had crouched low and hidden behind the Saints' offensive line. But once he did find Lewis, he rightly panicked. On the left side, Robey-Coleman said, the Rams only had cornerback Aqib Talib and a linebacker to cover two receivers.

In practice each week, Rams Coach Sean McVay would line up running back Todd Gurley II in the slot and put either of two wide receivers, Brandin Cooks or Robert Woods, in the backfield to prepare defensive backs for the kind of route combinations that would be likely if another team swapped the slot receiver and the running back. Now, it was clicking for Robey-Coleman.

“I was like, ‘Oh! Somebody is wide open!’ ” Robey-Coleman said. “I recognized it. I saw it. Nobody saw it. Nobody.”

His recognition had to happen fast, because the Saints executed a “quick break,” Robey-Coleman said, rushing to the line with the intent to snap it fast. As the Saints hiked the ball, Robey-Coleman left his position and sprinted across the field at Lewis, who ran a wheel route out of the backfield and down the right sideline.

“That was a long run,” Robey-Coleman said. “I just beelined it.”

When Robey-Coleman bolted, he left a safety to cover Kamara. Later, teammates told him Kamara would have been open if Brees had thrown that direction. Instead, Brees saw Lewis open down the right sideline.

“I just know I got there before the ball got there,” Robey-Coleman said. “And I whacked his ass.”

Robey-Coleman drilled Lewis. The NFL later admitted it should have been pass interference, and the league would have been fine if officials flagged him for a helmet-to-helmet hit. In the moment, Robey-Coleman thought he had hit Lewis early and expected to see a flag.

“I thought it was going to be a bang-bang play,” Robey-Coleman said. “But when I [looked] up, I thought it was P.I., because I didn’t look back for the ball. My teammates were like, ‘Think about if you were to look back, that could have been a pick-six.’ Because he threw it kind of short. But that didn’t happen. I seen his hands go up, and I just hit him, bro. I just hit him.”

Robey-Coleman deserved a flag, and he admitted it. The play should have effectively ended the game. Robey-Coleman and the Rams were lucky the referees blew the call, but that luck was only possible because of Robey-Coleman’s smart thinking and quick action.

“To be honest, I don’t know how I got there,” Robey-Coleman said. “I don’t know how I recognized it, either. To be honest with you, I was like, ‘Wow.’ ”

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