49ers elevate QB Adrian Martinez, WR Malik Turner

The 49ers elevated quarterback Adrian Martinez from the practice squad for Sunday's game against the Cardinals, the team announced.With Mac Jones expected to start for a second consecutive game with Brock Purdy nursing a toe injury, the 49ers will need Martinez available to back up Jones.The former UFL MVP. who signed with the 49ers on Aug. 28, has never played in a regular-season game. The 49ers also elevated wide receiver Malik Turner from the practice squad with Jauan Jennings questionable to play with an ankle injury and rookie Jordan Watkins (calf) ruled out.San Francisco also announced it has placed offensive lineman Spencer Burford on injured reserve with a knee injury. Burford will have to miss at least the next four games before he can return.Burford injured his knee last week and was already ruled out.