Standing in the jubilant visiting locker room about an hour after the Los Angeles Rams had won the NFC Championship, Nickell Robey-Coleman had still not seen the play. A reporter showed him a replay on an iPhone, and Robey-Coleman blurted out what everyone involved and everyone watching already knew.

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

Coleman had watched himself commit blatant pass interference late in the fourth quarter, a penalty the officials neglected to call. The play had seismic effects, both immediate and long-term. The New Orleans Saints had been in position to reach their second Super Bowl, and instead the Rams won the NFC title. The missed call convinced the NFL to make pass interference calls and non-calls reviewable on instant replay.

The play and its consequences will be revisited Sunday when the Saints meet the Rams for a rematch in Los Angeles. Both teams won their openers, and they are both among the favorites to return to the NFC championship game this January. As the Rams and Saints meet again, here’s a primer on the Nola No-Call that made their last game so indelible.

What happened on the fateful play?

With 1:49 left and the score tied at 20, the Saints faced 3rd and 10 from the Rams’ 13-yard line. Brees floated a pass to wide receiver Tommylee Lewis, who had lined up in the backfield and run a pattern down the right sideline. Robey-Coleman sprinted from the other side of the field and flattened Lewis well before the ball had arrived. “I just know I got there before the ball got there,” Robey-Coleman said. “And I whacked his a--.”

Was the no-call controversial?

Only in the sense that it inflamed the Saints and their rabid fan base, so much so that multiple lawsuits were filed against the NFL and Commissioner Roger Goodell. But everyone on both sides agreed it was an obviously missed call. “Nobody’s going to sit here and say it wasn’t pass interference,” Rams Coach Sean McVay said this week.

So what happened after the no-call?

Wil Lutz kicked a field goal on the very next play that sent the Saints ahead, 23-20.

Wait, the Saints went ahead afterward? Didn’t this play cost the Saints the game?

With a high degree of probability, but not certainty, yes. If the refs had called pass interference, the Saints would have had a new set of downs near the goal line. Coach Sean Payton would have called three quarterback kneels to kill the clock, and Lutz would have had a chip-shot field goal with no time left. Instead, the Rams drove down the field and kicked a field goal to force overtime, where they won.

Oh, so the Saints did get robbed.

Yes, but it’s not like they didn’t have chances to win. The Saints led, 13-0, after the first quarter. They may have put the game away early in the second had they not allowed an easy-to-see-coming fake punt. They could have stopped the Rams on the ensuing drive. They also got the ball first in overtime, but Brees threw an interception on a deflected pass. Still, the Saints would have almost certainly won had the obvious call been made.

How did the NFL respond?

Al Riveron, the league’s head of officials, called Payton immediately after the game and admitted the referees had missed the call. The league later admitted the referees also missed a helmet-to-helmet hit on the play, for which the NFL fined Robey-Coleman $26,739.

Goodell did not address the call for 10 days, until he held his annual news conference during the week of the Super Bowl.

“We understand the frustration of the fans,” Goodell said. “We talked to Coach Payton. The team, the players, we understand the frustration that they feel right now. And we certainly want to address them.

“Whenever officiating is part of any kind of discussion postgame, it’s never a good outcome for us. But we also know that our officials are human. We also know they are officiating a game in which they often have to make snap decisions under difficult circumstances. And they’re not going to get it right every time. As I say, they’re human.”

What is the play’s lasting impact?

It changed the legacy of Payton and Brees, who still only have one Super Bowl appearance. More tangibly, it convinced the NFL to change replay rules. With Payton leading the charge from his position on the NFL’s competition committee, NFL teams voted 31-1 to expand instant replay to pass interference. Coaches can challenge plays called pass interference and not called pass interference. It’s the first time judgment calls can be reviewed. The new provisions could be revisited after this season, because owners voted to make them a one-year trial.

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