San Francisco 49ers head coach Kyle Shanahan provided a plethora of injury updates during a conference call with the media on Friday. He noted two key defensive players who missed Thursday night's game and are not expected to play against the Houston Texans on August 18 – cornerbacks Richard Sherman and K'Waun Williams.

"Sherman, I have a feeling he's going to try to go, but I'd be very surprised if he played this week," Shanahan said. "We plan on holding him out ... K'Waun, don't expect to have K'Waun this week."

Sherman sustained a Grade 1 hamstring strain during team drills on August 3 and has not practiced since. He has been working hard all offseason to return from an Achilles injury sustained last November while with the Seattle Seahawks. Sherman was medically cleared at the start of training camp to fully participate in practices.

Williams left practice on August 5 after suffering an ankle injury.

The 49ers signed Williams in February of 2017. He appeared in 14 games with five starts while recording 54 combined tackles, five passes defensed, an interception, and a sack last season. The 49ers rewarded Williams with a three-year extension last September.

Defensive end Arik Armstead (hamstring) is another player who is not expected to practice this week.

Of those injured against the Dallas Cowboys on Thursday night, only linebacker Eli Harold is day-to-day. He sustained a knee contusion. Defensive lineman Solomon Thomas and tackle Garry Gilliam are in the concussion protocol. Linebacker Malcolm Smith (hamstring), tight end George Kittle (shoulder), and running back Matt Breida (shoulder) are expected to miss some time, but Shanahan is hopeful all will be available for Week 1 of the regular season.

Click here for a complete breakdown of all 19 of Shanahan's player updates.