Defensive lineman DeForest Buckner, the first-round pick the 49ers have leaned on heavily over the first quarter of the season, is day-to-day because of a foot injury, defensive coordinator Jim O’Neil said Tuesday.
“We’re still optimistic” Buckner will play Thursday against the Arizona Cardinals, O’Neil said.
That possibility seemed unlikely after Buckner sat out his second consecutive practice this week and wore a walking boot on his left foot. Still, the injury doesn’t appear to be long term, good news for a defense that already has lost inside linebacker NaVorro Bowman for the season.
The 49ers’ defensive line was believed to be the team’s deepest unit entering the season. Injuries to Arik Armstead (shoulder) and Glenn Dorsey (knee) have limited their snaps, however, forcing Buckner to play more than any other lineman. On Sunday against the Dallas Cowboys, for example, he played 70 of 76 snaps before being injured.
Buckner also leads San Francisco’s defensive linemen in tackles with 21.
Dorsey has appeared in the last two games after tearing an ACL in late November. He played 12 snaps Sunday, but O’Neil indicated Dorsey will get a heavier workload in the near future and could receive more snaps at nose tackle, where Mike Purcell mostly has played to this point.
“I think he’s getting to the point where he’s almost back to being 100 percent, and that’s something we’ve talked about,” O’Neil said.
A look at the defensive line’s snaps through the first four games: Buckner, 244; Purcell, 163; Armstead, 155; Quinton Dial, 139; Dorsey, 45; Ronald Blair, 37; Tony Jerod-Eddie, 6; Taylor Hart, 0.
Et cetera – Wide receiver Jeremy Kerley (ankle) practiced on a limited basis Tuesday after sitting out Monday’s session. Kerley leads the 49ers in receptions (18) and receiving yards (202).
▪ The Cardinals placed running back Chris Johnson on injured reserve because of a torn groin muscle. The team’s top running back this year has been David Johnson, who has 300 rushing yards and 210receiving yards.
▪ Cardinals coach Bruce Arians said quarterback Carson Palmer has “a chance” to play Thursday after suffering a concussion Sunday in a loss to the Los Angeles Rams. If Palmer doesn’t play, Drew Stanton will start his first game since 2014.