The 49ers announced Monday morning that linebacker Fred Warner has been placed on the reserve/COVID-19 list.
Warner had been a full participant in 49ers training camp, even earning 49ers Insider Matt Maiocco's award for best defensive player through the first 12 practices with full media access.
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If Warner indeed tested positive for coronavirus, he now will be subject to the NFL's COVID-19 protocols before he can return to the field. He must produce three negative tests before he can be allowed to resume football activity, and The Sacramento Bee's Chris Biderman reports the earliest Warner could return is Thursday.
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Running back Jeff Wilson Jr. began training camp on the list, but was activated just a few days later. No other 49ers player has been placed on the list in over a month.
Warner is expected to be the 49ers' starting middle linebacker once again in 2020, so hopefully for the organization, he can return to the lineup soon. The team's regular-season opener is less than two weeks away, as the 49ers will take on the Arizona Cardinals at Levi's Stadium on Sunday, Sept. 13.