THOUSAND OAKS, Calif. -- The scenario is far from what the Los Angeles Rams envisioned when they upgraded their secondary over the offseason and traded for cornerbacks Aqib Talib and Marcus Peters.

But as the Rams (3-0) prepare to play the Minnesota Vikings (1-1-1) on Thursday night at the L.A. Memorial Coliseum, they’ll be without Talib -- who was placed on injured reserve Wednesday, and also could be without Peters, who will be a game-time decision, Rams coach Sean McVay said.

Talib suffered a high-ankle sprain in a victory over the Los Angeles Chargers on Sunday and is set to undergo surgery. Peters injured his calf and left the locker room after the game in a walking boot, but could attempt to play Thursday, despite the quick turnaround.

“It has a lot of impact,” running back Todd Gurley II said about the loss of Talib. “... It's just part of the game and that's just how it is. One man got to step up whether whoever goes down. Just kind of got to move forward.”

It will be up to backups Sam Shields and Troy Hill, with Nickell Robey-Coleman remaining in the slot, to defend one of the NFL’s top receiving duos in the Vikings’ Adam Thielen and Stefon Diggs.

“It's a challenge any time your second-team people are in there,” defensive coordinator Wade Phillips said. “But we have a lot of confidence in those guys. We can call the same calls with those guys ... They're really fast and athletic. It's good to have them even though we don't have our starters.”

Thielen and Diggs have 2,651 receiving yards since the start of last season, the second most of any receiver duo over the same time span (Pittsburgh Steelers receivers Antonio Brown and JuJu Smith-Schuster have 2,850), according to ESPN Stats & Information.

There’s little doubt that Vikings quarterback Kirk Cousins, who has passed for 965 yards and seven touchdowns with two interceptions so far this year, will be eager to test Shields’ and Hill’s abilities.

“If they test them then they’re going to get interceptions just like Talib and Peters do,” defensive tackle Aaron Donald said. “We’ve got good players, man, from first team to second team so if one guy goes down another guy steps up. Got big shoes to fill but they’ll do it.”

The Rams have allowed a league-low 245 passing yards to receivers this season, according to ESPN Stats & Information. Talib, a five-time Pro Bowl selection, was acquired via a trade with the Denver Broncos in March and has seven tackles and two pass deflections. Peters, acquired in a trade with the Kansas City Chiefs, leads the league with 20 interceptions dating to 2015. This season, he has four tackles, a pass deflection and an interception that he returned 50 yards for a touchdown.

In a short time with the Rams, both have left an impression on teammates and a few lessons for their replacements.

“One thing that I’ve learned from them personally,” Hill said, “just go get the ball.”

Shields and Hill were inserted against the Chargers after Peters and Talib were sidelined. Shields played in 37 of 52 defensive snaps and finished with four tackles and a pass deflection. Hill played nine snaps.

Shields’ last start was in 2016, in a season opener with the Green Bay Packers, when he suffered a concussion, the fourth known serious head injury of his career. He was sidelined for the remainder of the season and sat out all of 2017 before he was cleared to return to football. The Rams signed him to a free-agent contract over the offseason.

This season Shields has five tackles and an interception. And after playing mostly on special teams through the first two weeks, he is eager to see significant time on defense.

“It’s an opportunity,” said Shields, who is in his eighth season. “Something that guys like us wait for. Sad, injuries like that happen. It’s a long season, and it’s the NFL so the next man has to be ready.”

Hill, a third-year pro, earned the confidence of his coaches when he started the final four games last season, including a playoff loss to the Atlanta Falcons.

“I’ve been in this position before,” Hill said. “With last year I grew from it, so I’m ready. I just got to continue to do what I’ve been doing and just stay focused.”