The MRI performed on the injured knee of San Francisco 49ers linebacker NaVorro Bowman revealed no remaining structural problems, but no determination has been made as to when he will be cleared to return to practice, according to a league source.

Bowman told ESPN following Sunday's game in New Orleans that he was still experiencing pain.

Defensive coordinator Vic Fangio said no indication had been given as to when Bowman would start practicing.

"I don't think it has," he said. "I haven't been kept up to date on that as far as, 'Hey, it's going to happen next week.' Nobody's said anything either way."

Bowman, who started the season on the physically unable to perform list, is recovering from surgery on his left knee after he tore the ACL and MCL in a devastating injury in the NFC Championship Game loss at Seattle in January.

49ers coach Jim Harbaugh said the team decided to have another MRI as part of the process of determining when Bowman might begin practicing.

Fangio did not rule out the possibility that Bowman would not play at all this season.

"I think that's a possibility," Fangio said. "I don't know that that's been decided or been the verdict, but I'm sure it's a possibility."

A source echoed Fangio's statements on Friday, saying there is a "real possibility" Bowman won't play this season, as he must begin practicing by Tuesday or else the 49ers will have to place him on season-ending injured reserve.

Information from ESPN NFL Insider Adam Schefter and ESPN 49ers reporter Paul Gutierrez was used in this report.