METAIRIE, La. — Right when it looked like Saints defensive coordinator Dennis Allen had built one of the more stifling units in the league, injuries have begun taking a toll.

Not only is starting end Alex Okafor done for the year, but the effectiveness of three other key starters who could try to play this week remains to be seen as New Orleans braces for the Los Angeles Rams’ fourth-ranked offense.

Saints rookie cornerback Marshon Lattimore did not practice Wednesday because of a left ankle injury that occurred Sunday in a victory over Washington. A first-round draft choice and the Saints’ top cornerback this season, Lattimore limped through the locker room wearing a protective boot on his lower left leg while it was open to reporters.

If Lattimore isn’t ready to play by Sunday, it’s safe to say Rams coach Sean McVay would see that as a considerable break for his offense.

“Lattimore’s a star. I’ve been extremely impressed in watching the tape of him — patience at the line of scrimmage and strength, short speed quickness, agility, all of the traits you look for in a corner,” McVay said. “He’s one of the most explosive players on the team, especially with some of the concepts coach Allen has in play. He’s a special player. I can’t say enough good things.”

The Saints could get safety Kenny Vaccaro and linebacker A.J. Klein back. Both players, who are veteran leaders for their position groups, said they expected to return to action after practicing on a limited basis Wednesday.

Vaccaro did not play last week because of a Week 9 groin pull that has sidelined him for two full games since, but said on Wednesday he was held out against Washington for precautionary reasons. Klein, who makes pre-snap formation calls for the defense, has missed one full game since hurting his ankle during a Week 10 victory over Buffalo.

Their absence, along with that of Lattimore, appeared to hurt a defense that gave up 456 yards and 31 points to the Redskins — statistically the worst performance by far for the unit during the Saints’ eight-game winning streak.

“Some of those scores we gave up were because of missed assignments and broken plays,” said Klein, who had to watch from the sideline. “When the crucial stops were needed later in the game, they came, which is obviously a positive, but we don’t want to be giving up that many points.”

During the first seven games of New Orleans’ winning streak, the Saints’ defense did not allow any opponent more than 347 yards, held five of its previous seven opponents to less than 300 yards — and three of them to 200 or fewer. The Saints also allowed 17 or fewer points in all but one of those games, the lone exception being when Detroit scored 38 with the help of defensive and special teams TDs.

Against the Redskins, Vaccaro said, “All the big plays that happened in the game were on us. It wasn’t anything they did spectacular.”

“We gave up almost 500 yards of offense and that hasn’t been us this season. A lot of it was communication,” Vaccaro continued. “We’ll get it corrected. We’ve got some guys coming back this week.”

Okafor, however, is one player who won’t return because of his torn Achilles. He could be replaced by rookie Trey Hendrickson, who has two sacks, two tackles for losses and a forced fumble in a reserve role.

Okafor had 4 1/2 sacks, five tackles for losses and two forced fumbles, and fellow defensive end Cameron Jordan called Okafor’s injury a “tremendous loss.”

Jordan added, however, that “it’s not like Trey’s coming in cold.”

Cornerback Ken Crawley, who has started the past seven games, also did not practice because of an abdomen injury, and the possibility of his and Lattimore’s absence led the Saints to bring back veteran free agent defensive back Sterling Moore this week.

Now New Orleans hits the road to face second-year quarterback Jared Goff, running back Todd Gurley, and an offense that averages 375.4 yards per game and ranks second in points per game with 30.3 — even after an uncharacteristic 24-7 loss to Minnesota last week.

Klein said coach Sean Payton made a point in Wednesday morning’s team meeting of touching on the Rams’ elite offensive rankings this season.

“Obviously this team has been very efficient on offense and it starts with Goff getting them into the right plays,” Klein said. “He’s definitely improved a lot from last season. He’s become a really good quarterback. And obviously with Gurley in the backfield they’ve got skill players across the board and can hurt you in different ways.”


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