49ers Pro Bowl defensive end Justin Smith is not expected to play Sunday night against the Seattle Seahawks because of an elbow injury and San Francisco is hoping he will be recovered enough to return for the postseason, according to a league source.

After Sunday night's game, San Francisco is hoping to be able to beat Arizona in the regular-season finale without Smith so it can give him another week of rest to heal for the postseason.

Smith has started 185 straight games, the longest active streak of any NFL linemen. He has never missed a game at any level.

San Francisco initially was going to list Smith as doubtful for Sunday night's game, but changed his designation to questionable.

Backup Ricky Jean Francois now is expected to start at Smith's right defensive end spot against Seattle.

Coach Jim Harbaugh, who indicated earlier in the week he expected Smith to play against the Seahawks, didn't elaborate on Smith's status Friday other than to say, "He's done quite a bit, rehab, strengthening, conditioning."

Information from The Associated Press was used in this report.