Rams lose kick returner Pharoh Cooper and backup Mike Thomas to injuries in opening win

The Rams’ season-opening victory over the Oakland Raiders came with a cost.

Pro Bowl kick returner Pharoh Cooper suffered an ankle injury that might require surgery, and backup Mike Thomas suffered a groin injury, coach Sean McVay said Tuesday.

“Pharoh’s ankle is definitely going to be something that’s going to limit him and keep him keep him out for at least a few weeks, and Mike will probably be the same,” McVay said during a news conference in Thousand Oaks.

Cooper emerged as a star last season. He averaged 27.4 yards per kick-off return – including one for a touchdown against Jacksonville that covered 103 yards. He also supplanted Tavon Austin on punt returns six games into the season and averaged 12.5 yards per return.

On Monday night, Cooper returned three kickoffs for 75 yards, and two punts for 12 yards in the Rams’ 33-13 victory over the Raiders.

He was injured during a third-quarter punt return.

“That’s a big loss for us,” McVay said.

Thomas, also a third-year receiver, has been a special teams mainstay. That he is Cooper’s backup, “makes it really complicated,” McVay said.

Receiver Cooper Kupp took reps as a punt returner during training camp in 2017. On Monday, he was in for one return and signaled for a fair catch.

McVay, however, said no decision had been made regarding Cooper’s replacement.

“Whether we handle that internally or we go outside for somebody else to figure that role out, those are things that we’ve kind of been discussing,” McVay said. “And in terms of making that final decision, that will be something we’ll probably decide on in the next day or so.”

Cooper and Thomas are not the only injury concerns.

Linebacker Mark Barron, who is earning $10 million this season, did not play in the opener because of an Achilles’ condition that has lingered despite offseason surgery.

The veteran’s availability for Sunday’s game against the Arizona Cardinals is “definitely questionable,” McVay said.

“It’s such a tough thing as far as being able to really project and predict what he’s going to be able to do,” McVay said.

Ramik Wilson started in Barron’s place against the Raiders and made four tackles. Safety Marqui Christian also filled Barron’s role at times against the Raiders, McVay said. Christian made three tackles.

Jump start

After producing only 98 yards in the first half, the Rams generated 267 yards in the second against the Raiders.

“You don’t blink, you don’t flinch,” receiver Brandin Cooks said after the game. “You go back out there and stick to your game, and understand it will come sooner or later.”

On Tuesday, when asked to assess his play-calling, McVay said there was room for improvement, and that he “really hurt” his team with his calls inside the 20-yard line.

“Just some of the play selections, putting us in some tough spots,” he said, adding, “Third down as a whole, I got to be much better.”

Etc.

Defensive tackle Aaron Donald reported the week before the opener, but he played 66 of 74 defensive snaps against the Raiders. Linebacker Cory Littleton, cornerbacks Marcus Peters and Aqib Talib and safeties Lamarcus Joyner and John Johnson played every snap. Defensive linemen Ndamukong Suh and Michael Brockers played 58 and 48 snaps, respectively…. With a short week following the Monday night game, the Rams did not practice Tuesday, and McVay canceled Wednesday’s workout to allow players extra rest. They will practice Thursday and Friday and do a walkthrough Saturday. “We’re going to treat it kind of like we did at the end of last year,” McVay said, adding that Wednesday would, “mostly be mental, and we’ll get a walk-thru-type setting and try to get a lot of reps, but take that physical toll off the players’ bodies.”… The Rams released offensive lineman Jeremiah Kolone from the practice squad and added offensive lineman Aaron Neary.

gary.klein@latimes.com

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