49ers place star linebacker Fred Warner on COVID-19 list

Fred Warner #54 of the San Francisco 49ers reacts to a defensive stop during the second quarter against the Pittsburgh Steelers at Levi's Stadium on September 22, 2019 in Santa Clara, California. (Photo by Daniel Shirey/Getty Images)

The San Francisco 49ers placed starting middle linebacker Fred Warner on the reserve/COVID-19 list Monday, less than two weeks before the start of the season.

Warner didn’t practice Sunday and then was placed on the COVID-19 list the following day. The list is used for players who either test positive for the coronavirus or have been in close contact with an infected person.

Coach Kyle Shanahan said he couldn’t get into details about whether Warner tested positive or how long he would be out because of NFL protocols.

“It’s just a good reminder that no one’s out of the woods,” Shanahan said. “When you go a few weeks with nothing happening, you start to feel pretty safe. It’s a reminder this stuff is out there.”

The Niners have now placed three players on the list this summer. Receiver Richie James Jr. and running back Jeff Wilson Jr. each had short stints on the list early in training camp. Wilson was on the list for five days and James for eight days.

The 49ers open the season Sept. 13 at home against Arizona.

“An incident like this, hoping that Fred is OK, is a quick reminder of how things can go and how we need to continue to be safe, take care of each other, protect each other, protect our family, continue to practice safe and healthy habits, social distancing,” teammate Arik Armstead said. “It’s definitely a wakeup call and a reminder for all of us that just getting in the rhythm of going through camp of how important it is to continue to be on top of those things.”

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Warner was an emerging star on San Francisco’s defense last season when the Niners won 13 games in the regular season and went to the Super Bowl. He excels in both coverage and against the run, as well as calling the defensive signals.

Warner had 118 tackles, seven tackles for loss, nine passes defensed, three sacks, three forced fumbles and an interception he returned for a touchdown against the Rams. Warner also had an interception in the Super Bowl loss to Kansas City.

The Niners are currently down two starting linebackers with Dre Greenlaw missing his second straight practice with a concussion.

Kwon Alexander is healthy at the weakside spot. Azeez Al-Shaair, Demetrius Flannigan-Fowles, Mark Nzeocha and Joe Walker are fighting for spots on the 53-man roster.

NOTES: LT Trent Williams got a day off from practice but should be back for the team’s next session Wednesday. ... CB K’Waun Williams returned to practice after missing time with a calf strain. ... TE George Kittle remains day to day with a hamstring injury.