San Francisco 49ers rookie wide receiver De'Zhaun Stribling will miss at least a month because of an ankle injury, sources told NFL Network.

Stribling sustained the noncontact injury in the second quarter of San Francisco's season-opening 27-7 victory over the Los Angeles Rams on Thursday night in Australia and did not return. Sources described it as a deltoid ligament sprain in his left ankle. He might ultimately need surgery, although his recovery plan was uncertain as of Sunday morning.

Niners coach Kyle Shanahan said Stribling avoided an Achilles tear but that further tests were needed to determine the diagnosis. San Francisco selected Stribling with the first pick of the second round (No. 33) in this year's draft. The former Ole Miss star had a strong training camp and earned a big role in the offense entering the season.