Sean McVay isn’t sure when Myles Garrett will return after surgery

Sean McVay and the Rams thought the situation was under control, or at least manageable.

Star edge rusher Myles Garrett first experienced knee discomfort and swelling during training camp, a condition that caused him to sit out the majority of team workouts throughout the weeks leading up to the season opener.

But Garrett failed to record a tackle, and was clearly not himself, in an embarrassing defeat by the San Francisco 49ers on Friday in Australia.

On Monday, Garrett was scheduled to have surgery, and he will sit out at least the next four games on injured reserve.

“Our job is to put our players and our team in positions to have successful outcomes,” McVay said Monday during a videoconference with reporters. “Thought we would take an approach where he’d be feeling good enough to go, contribute positive change and be the player that he’s capable of.

“But that wasn’t the case, and so the next right thing for us is to be able to get this thing fixed.”

Garrett, 30, will miss next Monday’s home game against the New York Giants, road games at Denver and Philadelphia and home game against the Buffalo Bills before he is eligible to return.

McVay did not have a timeline for his return.

“It’s all contingent on how do things go [Monday],” McVay said. “But I think it would be unfair to him, without having the totality of all the information, to put any sort of timeline on it.”

Garrett, a two-time NFL defensive player of the year, played only 40 of 65 snaps against the 49ers. McVay said the decision to pursue surgery was made after consulting with Garrett immediately after the game.

“We thought we were doing the right thing,” McVay said of the Rams’ attempt to manage the situation. “In hindsight, you’ll always be able to learn from it. I’ll never hang onto whether you want to say it was a mistake or just different things to be able to kind of change course.”

With Garrett out, the Rams could use a spark for a defense that gave up three touchdown passes and 174 rushing yards against the 49ers.

Will lineman Aaron Donald, who has returned from a two-year retirement, make his season debut against the Giants?

“We haven’t decided that yet,” McVay said. “He’s going to continue to work his process and we’ll see what that looks like.”

McVay said Donald’s situation is “totally separate” and “totally independent” of Garrett’s.

“It’s more about Aaron and how he can contribute to the collective,” McVay said. “What does that feel like with how he’s feeling to be able to resume 11-on-11 and being able to play and do the things that he’s capable of.”

In the meantime, the Rams will look to fill the void of Garrett’s absence with Josaiah Stewart, Desjuan Johnson and rookie Wesley Bailey.

Stewart, a second-year pro from Michigan, made six tackles and had one of the Rams’ two hits on 49ers quarterback Brock Purdy.

“He’ll be asked to step up,” McVay said, “as will everybody in that group.”

McVay speaks often about how adversity during a season is bound to come.

But for the Super Bowl-favorite Rams, it came early.

“I don’t have a crystal ball,” McVay said of anticipating when adversity will come. “I just know this: that these are the opportunities to really separate yourself with how you handle ‘em.”

The 49ers, the Seattle Seahawks and the Arizona Cardinals all won their openers, putting the Rams in last place in the NFC West.

It’s still early, of course, but the road to a spot in Super Bowl LXI at SoFi Stadium suddenly appears more challenging.

“That is over with,” McVay said of the loss to the 49ers. “That’s in our rearview mirror. We’re all eyes moving forward.”

Etc.

Linebacker Omar Speights suffered a hip pointer against the 49ers, McVay said. “We’ll kind of manage him throughout the week, but he’s feeling better than we anticipated,” McVay said. Linebacker Nate Landman sustained shoulder and thumb injuries, but McVay said he is expected to play against the Giants.