SANTA CLARA, Calif. (AP) Dylan Thompson has spent the majority of his rookie season as the scout team quarterback, posing as Aaron Rodgers, Carson Palmer or Russell Wilson in practice to prepare the starting defense.
Until this week. Now, his job is changing.
In one whirlwind weekend, Thompson went from practice squad to active roster and backup to San Francisco starter Blaine Gabbert. Colin Kaepernick, the quarterback who led the Niners to a Super Bowl just three seasons ago, injured his non-throwing left shoulder and underwent surgery Tuesday - and his time with the franchise could be over.
Thompson suited up for his first NFL game during Sunday's 29-13 loss at Seattle. He has to be ready for anything, because he is the next one up if Gabbert goes down.
''He showed up mature. He's got a maturity about him,'' coach Jim Tomsula said Wednesday. ''He's still a rookie, and he's learning. Every time you see the plateaus, you see him fight through them and then you see him get better. We're thrilled with the way he's approached things, the way he's worked.''
Even on the sidelines now, Thompson is more active because he must be a sounding board for Gabbert whenever needed or if asked about something he might be seeing on the field from his perspective.
''It was awesome. It really is,'' Thompson said. ''Just to know you work and you keep telling yourself your time will come if you just keep working and preparing. You never want it to be due to an injury or anything like that but when the opportunity's there for you to be able to move up, and in this case dress, it's a good thing for you personally.''
Thompson was an undrafted free agent out of South Carolina and was among those cut when Tomsula named his 53-man roster, yet Thompson stuck around on the practice squad.
He appreciates having the chance to learn from Kaepernick and Gabbert, who have been around the league for five seasons each now. They are locker mates and often have lunch together in the cafeteria at team headquarters.
Thompson has watched how both quarterbacks handled a difficult situation when the struggling Kaepernick was benched earlier this month and Gabbert was promoted ahead of leading the 49ers to a 17-16 victory against Atlanta on Nov. 8.
''Ever since I got here they've been great to me,'' Thompson said. ''You never know. People always tell you guys won't talk to you when you're a rookie, especially at quarterback. These two guys have been awesome for me, just really nice guys who have helped me. Any question I've had they've helped.''
In the preseason finale, when the reserves get their most playing time, Thompson completed 17 of 25 passes for 225 yards and two touchdowns with an interception and two sacks in a 14-12 win against San Diego.
That gave him a nice confidence boost going into the year that he could compete at this level, albeit in a game that didn't count for anything.
''He has done a tremendous job and I've tried to take him under my wing and kind of show him the ropes, because coming in as a rookie I know how that went and I was fortunate to have veterans kind of show me the way,'' Gabbert said.
Thompson understands that some quarterbacks benefit greatly from waiting their turn and learning behind the scenes rather than being thrust into the pressures of a starting role right away.
''At quarterback in particular, repeat experiences are huge in the development process,'' he said. ''Seeing guys go through things, certain looks, certain blitzes you might see in a game, and game-planning for certain things, the more of that you can get under your belt and obviously playing is huge.''
NOTES: When it comes to Tomsula's future, he said: ''We haven't had any conversations about any of that. We're in a performance-based business. All of us in it get it.'' ... QB Colin Kaepernick underwent surgery on his non-throwing left shoulder Tuesday in Colorado and DT Glenn Dorsey had an operation on his right knee at Stanford to repair a torn anterior cruciate ligament. Tomsula said his team struggled after Dorsey got hurt on the first defensive snap in Sunday's 29-13 loss at Seattle. ''I didn't like our body language,'' he said. ... Dorsey was placed on injured reserve and the Niners claimed LB Ray-Ray Armstrong off waivers from the Oakland Raiders. ... LB Ahmad Brooks told the team he is experiencing headaches and was placed in the NFL's concussion protocol.
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