The 49ers also placed offensive lineman Spencer Burford on injured reserve, meaning he would miss at least the next four games with a knee injury. Coach Kyle Shanahan said Friday that if 49ers wanted Purdy to be suited up as the emergency No. 3 quarterback, then Martinez, by league rules would have to be promoted to the 53-man roster as the backup rather than be called up from the practice squad.
Purdy also is dealing with a left-shoulder injury and won't practice Wednesday, but it is his unspecified toe injury that is a greater cause for concern. Shanahan allowed it to be classified as a turf toe injury although it is not by definition strictly on the bottom of Purdy's toe but also its side. The injury occured when tackled on a second-quarter scramble near the sideline, Shanahan said.