Ravens safety Kyle Hamilton strengthened his resume for defensive player of the year with a series of big plays Monday before falling to the ground and clutching his knee — for the second time in three weeks — late in Baltimore’s 33-19 win over the 49ers.

Against San Francisco, one of the top offenses in the league, Hamilton had two interceptions, three pass defenses and five tackles.

But with 9:43 left in the game, Hamilton made his fifth tackle, stopping a 22-yard play by Brandon Aiyuk, and did not get up. Hamilton held his knee and grimaced.

He was eventually able to walk off to the injury tent but spent the rest of the game standing on the sidelines. The Ravens are optimistic the injury is not serious.

“It doesn’t look bad for anybody,” coach John Harbaugh said after the game. “We will see tomorrow to ensure that. We’re fairly optimistic about everybody.”

A second-year player, Hamilton has emerged as one of the best players on the Ravens’ defense. His versatility is a key part of what makes the Ravens so effective: He can drop into coverage, makes open field tackles, stuffs the run and terrorizes quarterbacks on blitzes. And good luck throwing a screen pass to his side of the field.

Hamilton injured his knee against the Rams and did not return to the game, but he was back on the field for the team’s first practice after the game. He practiced all week with a knee brace and returned for the next game, which was against the Jacksonville Jaguars.

Weakened in the trenches

Two Ravens offensive linemen have been dealing with injuries and two more went down against the 49ers.

Tackles Ronnie Stanley and Morgan Moses have fought through lingering injuries and were given snaps off in recent games. On Monday night, right guard Kevin Zeitler and Patrick Mekari — who fills in at tackle — both left the game.

Zeitler suffered a thigh injury, and Ben Cleveland filled in for him.

Mekari is being evaluated for a head injury.

Jackson was sacked twice for 11 yards, and the Ravens rushed for 102 yards, their lowest total of the year.