It turned out that was all the Rams needed.
Kellen Clemens passed for two touchdowns, Zac Stacy rushed for 133 yards and a touchdown and the St. Louis defense harassed quarterback Drew Brees all day in building a 27-3 lead en route to a 27-16 upset of the Saints.
"We expect to be underdogs against the Saints," Clemens said. "We understand that. More importantly what this team has shown is such a drive to continue to work. There's a handful of teams right now that aren't going to the playoffs and unfortunately we're one of them. But I guarantee there is no other team in that group that is working as hard or still having as much fun as we're having."
Brees threw two interceptions in the first quarter for only the second time in his career, was sacked four times -- twice by defensive end Robert Quinn -- lost a fumble and did not pass for a touchdown until there was only 3:07 left in the game.
"This is what we knew," Brees said. "We knew we couldn't turn the ball over, that's a recipe for disaster. We knew we had to be able to stop the run and we were not able to do that early on. We had a field goal missed and a field goal blocked. We had opportunities to score points in the red zone and didn't. That can't happen. Penalties that prevent touchdowns at the end of the first half. That's a recipe for disaster. It will get you beat every time.
"We were in the red zone six times and came away with 16 points. That's not us. That can't be us if we want to play well and win."
The loss dropped the Saints to 10-4 while the Rams are now 6-8. The Saints can still clinch the NFC South and the No. 2 seed in the playoffs with a win next Sunday at Carolina, also 10-4, but the Saints know the road has not been kind to them this year. They are now 3-4 away from the Superdome, including only one win in their past five road games.
"Much has been written about how we have played at home and how we have played on the road and that's where it is right now," said Saints coach Sean Payton. "We came out here with a lot at stake ... and we can't line up to kick a field goal, we can't get the run stopped, we turned the ball over. We did everything we talked about that you can't do to get a road win.
"The way we played today was unacceptable. ... There wasn't a lot of things that were encouraging today to be honest with you."
One of the pre-game story lines was how Brees should be able to take advantage of a young and injury-depleted Rams secondary, but it didn't turn out that way.
On the Saints' first offensive play, Brees' pass intended for tight end Jimmy Graham was intercepted by safety T.J. McDonald, the first interception of his career. On the next play Clemens hit tight end Cory Harkey, who broke two tackles as he tight-roped down the right sideline for a 31-yard touchdown.
Brees also threw an interception at the goal line by cornerback Trumaine Johnson. Brees had only thrown one interception in his previous five games and just eight total this season.
Clemens capped a 93-yard, nine-play drive, aided by two personal fouls on the Saints for unnecessary roughness, with a 4-yard scoring pass to tight end Lance Kendricks.
It was the first time in Clemens' career that he has passed for two touchdowns in the same quarter.
"Both the early turnovers really helped us put them in a hole and then we played the rest of the game with time on our side," said Rams coach Jeff Fisher.
Stacy's 40-yard touchdown run increased the St. Louis lead to 24-3 with 4:10 left in the first half, and gave him 106 yards in the first half -- his third game of more than 100 yards during his rookie season.
An apparent 8-yard touchdown pass from Brees to wide receiver Lance Moore in the closing seconds of the half was wiped out by another penalty against the Saints, and the Rams then blocked a 36-yard field goal attempt by Garrett Hartley.
Greg Zuerlein's second field goal of the game, from 35 yards, increased the lead to 27-3 with 2:42 left in the third quarter.
Brees scored New Orleans' first touchdown on a 1-yard quarterback sneak with 11:25 to play in the game, but the attempt for a two-point conversion was stopped by the Rams. He finally passed for a 5-yard touchdown to wide receiver Marquis Colston with 3:07 remaining