Other 49ers that will not play in tonight's game are WR DeAndre Smelter, DB L.J. McCray, FS Eric Reid, DE Glenn Dorsey, and DE Arik Armstread.
Kaepernick was held out of team drills on Thursday and Friday, the latter being a joint-practice with the Texans. He was suffering from "arm fatigue" and a sore shoulder. Prior to that, the two quarterbacks had been splitting reps equally during training camp practices and reportedly will continue to do so in preseason.
Earlier this month, Kelly said that preseason would be huge for evaluating both Gabbert and Kaepernick. "To make a fair evaluation, they have to both get reps with the ones," he said.
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"I'll tell you what, both guys are doing a good job," said offensive coordinator Curtis Modkins earlier this week. "They are both competing their tails off. In the classroom, on the field, they are both doing a good job. I wouldn't say any one is ahead of the other right now. I think as we get into the preseason and we get to playing live games, those things will start happening, but right now I wouldn't say anyone is ahead of anybody. I just think they are both progressing like we want them to and both have been really good."
Kaepernick started the 2015 season as the 49ers' starting quarterback. He tore a ligament in his throwing hand's thumb during an October 22 loss to the Seattle Seahawks. During his next game, a November 1 matchup against the St. Louis Rams, Kaepernick said that he suffered a bone bruise and cracked cartilage. That game would be his last of the season before being benched in favor of Gabbert and eventually being placed on injured reserve.