The San Francisco 49ers are hoping to get Trent Williams back from injury this week for a massive game with the Jacksonville Jaguars.

Yet as of Wednesday, they are no closer to knowing if this hopes will be realized.

Kyle Shanahan confirmed in his press conference that All-Pro left tackle Williams would be a non-participant in the first full practice of the game week. The 49ers had a light bonus practice on Monday after returning from the bye week.

Williams usually has Wednesday as a veteran's rest day, so him not practicing is no surprise.

While Shanahan expressed hope of Williams being able to practice on Thursday, his comments on the specifics of the injury should prompt concern.

Asked if there is more going on with Williams' ankle than the initial injury, first thought to be a low ankle sprain, that he suffered in the Week 6 defeat to the Cleveland Browns, Shanahan replied: 

"Yeah, I think obviously there is. He's got a lot of history in there with stuff. It didn't show up as a high or anything like that, but when you've had that over your career, there are a number of things with how it's taken longer than expected to heal, it's more than a low."

Williams played through the injury in the loss to the Browns but has since missed defeats to the Minnesota Vikings and the Cincinnati Bengals, games in which the rushing attack often struggled and the pass protection failed Brock Purdy in key moments.

Swing tackle Jaylon Moore filled in for Williams in each of those games and fears of the 49ers' losing streak stretching to a fourth game will rise if he has to do so again versus a Jaguars defense that ranks third in the NFL by Expected Points Added per play.

49ers make change with defensive coordinator Steve Wilks ahead of Jaguars game

They want him closer to his players.