The San Francisco 49ers held a bonus practice on Monday as they return from the bye week and had mixed news on the injury front with two of their most important offensive stars.

As he indicated would be the case last week, wide receiver Deebo Samuel returned to practice having missed the last two games with a hairline fracture in his shoulder.

However, All-Pro left tackle Trent Williams was not involved in the practice, though he was seen on a side field throwing a ball around.

Both Samuel and Williams were injured when the 49ers lost their first game of the season at the hands of the Cleveland Browns in Week 6. Williams played through his injury while Samuel left the game in the first half.

The 49ers have since lost to the Minnesota Vikings and Cincinnati Bengals with Samuel and Williams on the sideline, the absence of the latter proving critical as pass protection has faltered in key moments while the run game has taken a step back.

Logic suggests the 49ers are likely just being extra careful with a veteran who is crucial to their hopes of going all the way to the Super Bowl this season.

The Niners have a day off on Tuesday and Williams usually gets veteran's rest on Wednesdays, but the concern that he could miss the Week 10 matchup with the Jacksonville Jaguars will go up if he is not out there for Thursday's practice.

49ers’ midseason grades: The offense is the clear star of the show

There’s still room for improvement.