Unsurprisingly at this early part of the week, the San Francisco 49ers are playing it safe with their stars.

Speaking before Wednesday's practice and revealing their preliminary injury report, head coach Kyle Shanahan said both George Kittle (hamstring) and Nick Bosa (hip) would miss the opening session of their preparations for Sunday's clash with the Seattle Seahawks.

All-Pro left tackle Trent Williams got his usual veteran's rest day, though Shanahan added he is also dealing with an ankle issue.

Asked about his concern level over Kittle and Bosa, Shanahan said it was "not high", expressing his belief that the former will be able to practice on Thursday.

Punter Mitch Wishnowsky was also listed as DNP. Wishnowsky is dealing with a back problem and the 49ers on Tuesday signed Pat O'Donnell to the practice squad as insurance.

Running back Christian McCaffrey was limited following his long-awaited return from Achilles tendinitis in last Sunday's win over the Tampa Bay Buccaneers. Shanahan said McCaffrey's restricted involvement in practice is part of his maintenance plan as the reigning Offensive Player of the Year hopes to avoid a recurrence of a tricky injury.

Also limited were Jon Feliciano (knee) and Chris Conley (hamstring). Veteran interior offensive lineman Feliciano had his practice window opened last week having spent the entire year on injured reserve.

Rookie cornerback Renardo Green is good to go after suffering a toe injury against Tampa Bay. Yetur Gross-Matos (knee) practiced in full, pointing to him making his return to provide a much-needed boost to San Francisco's edge depth.

All-Pro corner Charvarius Ward remains away from the team following the tragic death of his one-year-old daughter.

49ers injury report

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