Myles Garrett has a knee injury.

He needs surgery.

Coach Sean McVay spoke on Monday.

He said the Rams lost their first game.

After that game, it was clear Garrett could not keep playing.

Garrett had no tackles and no sacks.

The Rams lost 27-7 to the San Francisco 49ers.

The game was in Melbourne, Australia.

Garrett played 61.5% of the defensive snaps.

McVay said the team thought Garrett could play through the knee problem.

But after the real game, McVay said, "maybe that's not the case."

Garrett is on injured reserve.

He will miss at least four games.

McVay had no new timeline after that.

He is waiting for the surgery results.

Garrett missed much of training camp.

The team said it was knee swelling.

McVay has not explained the exact injury.

The Rams traded for Garrett from the Cleveland Browns in June.

They sent pass rusher Jared Verse and three draft picks.

Before the game, Garrett said he felt "ready."

He said he wanted to win the Super Bowl.

He also wanted to be AP Defensive Player of the Year again.

McVay said Garrett's absence will not change when Aaron Donald returns.

Donald did not travel to Australia.

He is working back into shape.

He was out of football for two seasons.

McVay said it is too early to know if Donald will play next Monday.

The Rams play the New York Giants at home.