Harbaugh: Colin is playing so well he overshadows other guys
Chris Culliver registered two interceptions, one forced fumble, one fumble recovery, and 43 tackles last season. (USA TODAY IMAGES)
Nnamdi Asomugha's role may increase significantly if Chris Culliver is forced to miss an extended amount of time. (AP)
Editor's note: Training camp is underway. For all the latest news from Santa Clara, check out our 49ers training camp page.
SANTA CLARA -- Cornerback Chris Culliver, who sustained a potentially serious left knee injury in 49ers practice on Thursday, was scheduled to undergo an MRI examination.
Coach Jim Harbaugh said he has not received word on the extent of Culliver's injury. "He's at Stanford getting an MRI," Harbaugh said.
Culliver played 63.2 percent of the 49ers' defensive snaps last season as the third cornerback behind Tarell Brown and Carlos Rogers.
Tramaine Brock and Nnanmdi Asomugha have played well in the first week of camp. Harbaugh refereed to some "eye-popping plays" from Asomugha.
The 49ers might also revisit acquiring veteran Eric Wright, whose trade from Tampa Bay to the 49ers was voided last week due to a failed physical.
Earlier on Thursday, the 49ers received word that All-Pro linebacker Patrick Willis would be sidelined with a broken right hand. He was a spectator at practice Thursday with a small black cast on his hand.
When asked if he thought Willis would be available for the 49ers' Week 1 game against the Green Bay Packers, Harbaugh answered, "Yes. Yes."