Dee Ford and Nick Bosa were supposed to be the symbols of this team's defensive renaissance. Ford, who has a history of injuries, is out after a procedure to his knee. Bosa is highly uncertain to be ready for Week 1 due to an ankle injury, following the hamstring issue that forced him to miss OTAs. Cornerbacks Jason Verrett (ankle) and K'Waun Williams (knee) may also be out for the opener, depleting a cornerback group full of questions after Richard Sherman. Projected starting slot receiver Trent Taylor (foot) is expected to miss the start of the season. Swing tackle Shon Coleman (ankle) is likely out for the year, while starting center Weston Richburg (knee) hasn't practiced once all offseason after a disastrous first season in San Francisco. Running back Jerick McKinnon (knee) could start the year on injured reserve, although that's one position where the 49ers have plenty of depth. At least for now.