Right tackle Anthony Davis will be not be available for the 49ers in Sunday's season opener after sustaining a hamstring injury.
Davis returned to practice prior to the team's third preseason game against the Chargers after recovering from offseason shoulder surgery, but was officially ruled out Friday after not practicing this week.
It's unknown when Davis suffered his hamstring injury, but it's likely a product of his prolonged time off the field and transitioning back to football shape in a short amount of time.
Presumably, Jonathan Martin would step in at right tackle for Davis, as he did in all four preseason games. But Jim Harbaugh, who has vowed to remain tight-lipped on personnel decisions this season, wouldn't say who will start on the right side of the offensive line.
"We’re not going to go into what exactly is going to take place,” he said.
Right tackle isn't the only position in question. Right guard Alex Boone returned from his offseason-long holdout last week prior to getting a new two-year, $6 million deal.
The coaching staff has said Boone is in good shape, but there are questions about his knowledge of coordinator Greg Roman's new-look offense.
"(Boone) missed some time, but he looks good," Roman said. "I think he’s jumped back into the offense. We’ve cut way back on some stuff, so the stuff we’re doing is pretty manageable for him."
The 49ers will have to make a roster move to get Boone back on to the 53-man roster - a move Harbaugh said would come Saturday. The team broke training camp with reserve Dillon Farrell on the 53 over veteran Adam Snyder and former practice squad players Ryan Seymour and Carter Bykowksi.
Center Daniel Kilgore is slated to make his first career start Sunday after backing up Jonathan Goodwin for the last three seasons. Goodwin, 35, signed with the Saints this offseason.
The 49ers are taking on a defense looking to rebound from one of the worst seasons in league history. The Cowboys allowed the third-most yards of all time, including six games of allowing at least 450 yards of total offense. They have finished 8-8 under head coach Jason Garrett in the last three seasons.
MCDONALD TO PLAY
Despite his arrest last weekend on alleged domestic violence charges, defensive lineman Ray McDonald will play Sunday, Harbaugh said.
"Two principles are woven together here. I feel like the way the facts are and what’s known that he has the liberty to play in the game," he said.
Both Harbaugh and general manager Trent Baalke have harped on "due process" during their sessions with the media this week when discussing the issue. The league has yet to suspend McDonald after changing its policy on domestic violence last week.
Amid the fallout from Ray Rice's two-game suspension for his domestic violence arrest in February, commissioner Roger Goodell issued a letter to all 32 teams stating a first offense will result in a six-game suspension without pay. A second: a lifetime ban from the league.
According to a report from the Sacramento Bee, police have yet to turn in a final report to the Santa Clara County District Attorney's Office regarding McDonald's arrest. If charges are filed, they likely won't come until after Sunday's game.
Baalke said the team was exhausting all resources at its disposal to find out exactly what happened at McDonald's home during his 30th birthday party last Saturday night and into Sunday morning.
Tight end Vernon Davis intimated that "75 percent" of the team could have been there, potentially giving the 49ers a volume of witnesses to gather information from.
Given their repeated "no tolerance" stance on domestic violence, it's likely they believe in McDonald's innocence. Otherwise they would be risking another serious black eye to the organization by allowing McDonald to play. San Francisco has led the NFL in arrests since Harbaugh became coach in 2011.
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