First, the good news. Shanahan confirmed that rookie defensive end Nick Bosa will play on Sunday.
"Yeah, he's ready to go," Shanahan said on the "Murph and Mac" show. "We knew it was a tough injury. We weren't sure if we were going to get him back this week because any time you have a high-ankle (sprain), it could be anywhere from four to eight weeks. It's getting right up to four, and he's had three good practices this week, and he's ready to go."
Shanahan believes Bosa is the type of player who can make an impact right away.
"The way he plays, the way he's practiced, he just got back this week, but we wouldn't put him out there if he wasn't ready to go," Shanahan continued. "We expect him to make an impact, and we expect a number of our guys to."
Shanahan also provided an update on injured defensive back Jimmie Ward, who broke a finger during practice on Wednesday.
"Jimmie's most likely not going to play," Shanahan said. "... I've got to talk to the doctors here in about an hour, but I'd be very surprised if he played. He broke his finger, got it caught up in a jersey in practice, ended up having surgery on it yesterday.
"Jimmie's a guy, he's adamant he wants to play with a cast on and everything. That's what we're still trying to wait to see for sure on but I think we're going to have to wait a week before we let him play with a cast on because any time you get surgery, just to do that right away, you always deal with the risk of infection and things like that, so we've got to play that a little safe.
"Don't know for sure but I'd be surprised (if he played)."
Shanahan didn't want to reveal what the absence of Ward means for the defense on Sunday.
"It's a very big deal for (opposing) offenses to know who the safeties are, who the nickel back is, all that stuff," Shanahan added. "They need to know those numbers going into games so they know how to target things and get the O-line on the right people. I'd rather them find out on the first play rather than today listen to this show."
You can listen to the entire conversation with Shanahan below.
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