Colt McCoy entered training camp as the favorite for the backup job, but injury and middling production appears to have opened up the competition. Niners coach Jim Harbaugh said Wednesday that McCoy, Scott Tolzien and rookie B.J. Daniels have received an equal number of snaps during practice this week.
The 49ers probably aren't confident Daniels would sneak through waivers, so his spot should be safe if Wallace comes aboard. The same cannot be said for McCoy and Tolzien, who both appear extremely vulnerable at the moment.