LOS ANGELES -- In case it wasn't obvious enough by the situation -- fourth-and-1, one-score game, start of the fourth quarter, ball near field goal range -- Mark Barron confirmed it right before the snap. The veteran inside linebacker saw Dallas Cowboys wide receiver Noah Brown go in motion and set up right behind tight end Rico Gathers, a dead giveaway that an inside run was coming. The Los Angeles Rams' defense had spent the entire week focused almost exclusively on containing Ezekiel Elliott, simultaneously fighting the incessant notion that their star-studded unit was generally inept against the run.

When the biggest moment presented itself at 7:40 p.m. PT on Saturday, they were ready.

Ndamukong Suh was the first to get free.

"I saw what they wanted to do, played off the center and tried to close up the gap," Suh said. "My hands were tied, so I just went in head first."

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Suh's helmet was the first object to make contact with Elliott, right before a mob of his teammates swarmed in to help, taking possession away from the Cowboys and changing the complexion of an eventual 30-22 victory that saw the Rams advance to the NFC Championship Game and flip an entire narrative on its head.

The Cowboys were supposed to dominate the run on both sides, with the NFL's leading rusher in their backfield and a stout defense that had allowed only 3.8 yards per carry. But it was the Rams' offense, suddenly a two-back system with Todd Gurley and C.J. Anderson, that amassed 273 yards on the ground. And it was the Rams' defense, fresh off surrendering an NFL-worst 5.1 yards per carry in 2018, that limited the Cowboys to a mere 50 rushing yards, their lowest output all season.

"We knew we could stop the run -- it was just a matter of doing it," Barron said. "It really wasn't that hard. It was everybody being where they're supposed to be and doing what they're supposed to be doing. It was really simple."

The Rams are going to need a lot more of that on Sunday (3:05 p.m. ET, Fox) when they face a New Orleans Saints offense that features the devastating two-prong attack of Alvin Kamara and Mark Ingram.

The Rams are going to need more performances like these from Suh.

On Saturday night, in what became the Rams' first playoff victory at Los Angeles Memorial Coliseum in more than 40 years, Suh jumped off the film in a way he rarely had all season. The numbers -- two quarterback hits, one tackle for loss -- weren't gaudy. But Suh displayed the quintessential balance of ferocity and discipline, consistently winning at the point of attack and constantly clogging holes to help keep Elliott at 2.3 yards per carry.

Suh was given the highest grade on the Rams' defense by Pro Football Focus, which had him with four pressures in 30 pass-rush snaps and a run-stop percentage of 11.8.

After a mostly quiet regular season, Ndamukong Suh led a Rams defense that limited Ezekiel Elliott and the Cowboys to just 50 rushing yards. Sean M. Haffey/Getty Images

When it mattered most, he might have been the best player on the field.

"It's a great compliment," Suh said late Saturday night. "At the end of the day, how I look at it is I'm still going to play at an elite level. Given opportunities, which I was given today, I'm going to make plays. This atmosphere, being at home, great fans, and it's the playoffs -- you bring it all or you go home. And I'm not trying to go home anytime soon."

The Rams stacked the box, as expected, against the Cowboys. They played in their base set (four defensive backs, two interior defenders and two edge rushers) on 35.3 percent of the snaps in which the Cowboys ran "11" personnel (one running back, one tight end, three wide receivers). During the regular season, the Rams were in base sets on only 8.2 percent of opponents' "11" personnel snaps.

"We knew that they were going to run, try to get Zeke loose," Rams outside linebacker Samson Ebukam said. "And we knew that if we could contain Zeke, the game was basically over."

At the nine-minute mark of the first quarter, Suh sprinted from the hash marks to the numbers to stop Elliott for no gain. At the 10-minute mark of the third quarter, Ebukam set the edge to help Suh slam Elliott for a 2-yard loss. Nine minutes later, Aaron Donald went basically unblocked into the backfield and stuffed Elliott for a loss of 4. And in the final minutes of regulation, inside linebacker Cory Littleton sniffed out a shovel pass in the flat and tackled Elliott for another 2-yard loss.

The Rams outgained the Cowboys 459 yards to 308, accumulating 11 more first downs and running 21 more offensive plays.

But it was their defense, agonizingly inconsistent throughout the year, that finally made its presence felt.

"We arrived," Rams coach Sean McVay said, "and you could feel our guys at the point of contact."

The Rams face an entirely different challenge against the Saints.

Their run game is just as lethal, but their passing attack, led by future Hall of Famer Drew Brees, commands respect. The Rams can't load the box against the Saints like they did against the Cowboys. They'll need more coverage in their backfield, which means their interior players must stay disciplined in their gap assignments.

"It's going to be a huge point of emphasis this week," McVay said. "They can beat you both ways -- they can run it or they can throw it -- and that's what really presents such a great challenge."

Suh came over on a one-year, $14 million contract and has been overlooked with the Rams, mostly because his teammate, Donald, put together a historically great regular season with 20.5 sacks. But Suh still compiled 4.5 sacks and the metrics say he defended the run well, even while adjusting to operating as a nose tackle.

On Saturday, Barron felt Suh played his best game of the season.

"To me he did," Barron said. "He was just dominant."

"You definitely felt his presence," McVay added. "I thought he pursued the football outstanding. I thought he was able to get [into the backfield] all night, and I thought that affected some of the different things that they were talking about, so I think he was outstanding in those early downs. When he's able to do that, it makes a huge difference. I thought he really came with a great focus and concentration this week, and I think it showed up with the way that he was able to play."