Jim Harbaugh confirmed Monday an MRI revealed rookie center Marcus Martin did not suffer an ACL injury in Sunday's game, and will likely return to the team at some point during the regular season.
"It looks that way," Harbaugh said, while declining to comment on a time frame for the injury.
Martin, 20, was the team's No. 2 center behind new starter Daniel Kilgore and had to be carted off the field in the second half of Sunday's 21-7 win over the San Diego Chargers. The San Francisco Chronicle reported Martin would miss eight weeks with a kneecap injury.
The injury, while it won't keep Martin out for the season, puts the 49ers in a short-term bind.
San Francisco enters Thursday's preseason finale in Houston thin at the position. It's likely reserve interior lineman Dillon Farrell will get playing time at center, as he did in the preseason opener while Martin was out dealing with an ankle injury. Harbaugh said Adam Snyder and Joe Looney can also play center.
The 49ers are already thinner along the interior offensive line than they would like to be as right guard Alex Boone's holdout continues to linger towards the regular season. Martin was another body capable of playing right guard in case anything happened to Joe Looney, who has been starting in Boone's absence.
Martin becomes another option for the 49ers to go on Injured Reserve with the designation to return, joining nose tackle Glenn Dorsey, who sustained a torn biceps tendon Aug. 1. Only one player can be given the return designation each season and can be eligible to return after eight games without taking a spot on the 53-man roster.
The 49ers' ninth game of the season is Nov. 9 visiting the New Orleans Saints.
Martin was taken in the third-round of May's draft and was viewed by many as the best center available after three seasons at USC.
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