Sherman strained his calf late in Sunday's 24-20 loss to Arizona and was placed on IR when the injury didn't get better right way. He will have to miss at least three games before he can return but the Niners are hopeful it won't be a longer-term injury.
Kittle sprained his knee in the same game and won't take part in a full practice this week. Coach Kyle Shanahan said there's a possibility Kittle could participate in the lighter Friday practice before the team leaves to play the New York Jets on Sunday.
Shanahan also said Kittle could play even without practicing all week.
These are the latest in a series of injuries that have hampered the defending NFC champion 49ers early this season.
“It’s a challenge, but you always have something like this each year,” Shanahan said. “It’s hitting us pretty hard right now. ... It’s a challenge and some stuff is still up in the air. It’s not our first time doing this. You got to be prepared whatever way it ends up on Sunday.”
San Francisco played the season opener without two of its top receivers in Deebo Samuel (foot) and Brandon Aiyuk (hamstring), as well as its top two centers in Weston Richburg (knee) and Ben Garland (ankle).
Backup cornerback Ahkello Witherspoon is in concussion protocol as well after getting hurt on the final drive last week and Jason Verrett remains sidelined by a hamstring injury.
“We’ve dealt with this before,” quarterback Jimmy Garoppolo said. “I think every team, you’ve got to deal with your injuries. ... I think it’s really just about getting the guys out there you feel confident in who you know what they’re going to do and will do it on Sunday.”
Sherman has been one of the league’s top cover cornerbacks for the past decade. He was a second-team All-Pro last season when he locked down the defensive left side of the league’s top pass defense.
He fared better than anyone else on San Francisco’s defense in Week 1 against DeAndre Hopkins, limiting him to three catches for 22 yards on 15 pass plays. Hopkins had 14 catches for 151 yards overall in Arizona’s 24-20 win.
The 49ers begin the week with Emmanuel Moseley and Dontae Johnson as the only two healthy outside cornerbacks. Johnson was promoted from the practice squad Wednesday.
“I know guys are ready to step up,” linebacker Fred Warner said. “It’s always next man up in this league. I think guys are ready and if we put the right week of practice in like we know we should, we should be firing on all cylinders this week.”
San Francisco also could be without backup receiver and returner Richie James Jr., who injured his hamstring in the game
The Niners agreed to a deal with receiver Mohamed Sanu on Tuesday for more depth at that spot. Sanu must go through the COVID-19 protocol before he will be able to start practice Friday but is taking part in virtual meetings.
Sanu played one season for Shanahan in Atlanta and is familiar with the offense.
“Mo will do his part. He’s a pro,” Shanahan said. “He’ll learn his responsibilities, what he has to do. Basically the decision of whether he’ll play or not probably is going to depend on the health of our other receivers and how that goes.”
NOTES: The team signed CB Brian Allen and CB Christian Angulo to the practice squad and placed CB Tim Harris Jr. on the practice squad injured reserve list with a calf injury.
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