Rams’ Connor Barwin to be out a few weeks after undergoing forearm surgery

Rams linebacker Connor Barwin, a veteran who has provided performance and leadership during the team’s surge to the top of the NFC West, had forearm surgery Monday and will be sidelined a few weeks, coach Sean McVay said.

Barwin was injured during the first half of Sunday’s 26-20 victory over the New Orleans Saints at the Coliseum.

Rookie Samson Ebukam will start in Barwin’s spot Sunday against the Arizona Cardinals at University of Phoenix Stadium.

“You lose a lot,” McVay said of a lineup devoid of Barwin, a ninth-year pro, “but in his absence, we’re looking forward to seeing Samson step up.”

Barwin, 31, has 25 tackles, including four sacks, for a Rams defense that neutralized quarterback Drew Brees and the Saints’ high-powered offense in a win that improved the Rams’ record to 8-3.

The 6-foot-4, 255-pound Barwin was signed as a free agent after four seasons with the Houston Texans and four with the Philadelphia Eagles. He was voted a team captain and has started every game this season.

“You look at a guy who was brought in here his first year and voted a captain by his teammates,” McVay said during a news conference in Thousand Oaks. “That says a lot about the type of person he is and the way he goes about his business.”

McVay said a small plate was inserted in Barwin’s left forearm to aid healing. He did not give a definitive timetable for Barwin’s return.

Ebukam, 6-3 and 240 pounds, replaced Barwin against the Saints. The fourth-round draft pick from Eastern Washington sacked Brees for an 11-yard loss. Ebukam also had a sack and forced a fumble against the Texans.

“He’s continuing to understand the nuances of the system and what he’s being asked to do,” McVay said. “I think he’s demonstrated that growth.”

Barwin has been “a huge influence” on Ebukam, McVay said. “You look at a true mentor that really helped bring him along,” the coach added. “You look at the growth that Samson has displayed, especially over the last couple weeks.”

Barwin and Ebukam helped the Rams control a Saints offense that entered the game ranked first in yardage, second in passing and third in rushing and scoring.

The Rams won without forcing a turnover, though they missed several opportunities for interceptions. “Definitely could have been 10 times better if we would have caught some of those,” linebacker Alec Ogletree said.

The Rams lose Barwin but they could regain some secondary strength against the Cardinals. Cornerback Nickell Robey-Coleman, who was sidelined against the Saints because of a thigh injury suffered in the previous week’s defeat at Minnesota, was “90% to 95%” ready to return, McVay said.

Running back Lance Dunbar, who was inactive against the Saints because of a knee injury, could return to practice this week, McVay said. Running back Malcolm Brown (knee) also is getting close to returning…. McVay was a Washington Redskins assistant when Chip Kelly was the Philadelphia Eagles’ head coach. McVay said he was looking forward to meeting Kelly, UCLA’s new coach. “I’m a fan of coaching,” McVay said, “so anytime you get a chance to sit down and talk some football with some other coaches — and there’s a little bit more willingness to share because maybe you’re not in the same arena or in the environment — that would be something I’d love to be able to do if he was open to that.” … The Rams will resume practice Wednesday.

gary.klein@latimes.com

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