Injury to 49ers' top rookie is a potentially massive blow

Ji'Ayir Brown's emergence following a season-ending injury to Talanoa Hufanga has been a development of underrated importance for the San Francisco 49ers during the second half of the season.

However, the 49ers may now need to find a replacement for their rookie top pick after head coach Kyle Shanahan revealed the third-rounder had suffered a knee sprain.

That injury kept Brown out of Wednesday's walkthrough practice as the 49ers prepare to face the Washington Commanders on a short week.

Asked about the injury in his Wednesday press conference, Shanahan indicated it could be a long-term injury for the former Penn State star.

"There's concern [of it being long term]. We're not ruling him out this week, but there's concern, that's why he can't go today," Shanahan said.

While Brown struggled with open-field tackling in the 49ers' 33-19 loss to the Baltimore Ravens on Christmas Day, he has been largely excellent since taking over for Hufanga, who went down in the Week 11 win over the Tampa Bay Buccaneers. Brown clinched that victory with an endzone interception and also had three pass breakups.

He recorded another interception against the Seattle Seahawks in Week 14 and has consistently demonstrated the awareness, athleticism and playmaking ability that led the 49ers to trade up for him.

Any prolonged absence would create a huge hole for the 49ers going into the postseason, one that would most likely be filled by veteran Logan Ryan, who signed with San Francisco on December 6. Shanahan also indicated that practice squad safeties Erik Harris and Tayler Hawkins could be options, along with slot corner Isaiah Oliver.

Brown's speed in adapting to the NFL game after taking over for Hufanga prevented safety from turning into a potential weakness. If Brown is out for an extended period of time, the 49ers need to find another solution that has the same impact.