Something had changed.
The San Francisco 49ers quarterback spent much of his offseason in Arizona working with former NFL QB Kurt Warner to better himself on the field and in his approach.
''My God, what have you been doing?'' Davis said Friday of his reaction when he and Kaepernick worked out together a day earlier. ''No, seriously, he was working on his drop back and I was like, `Who is that?' You guys are in for a treat. He looks like a totally different guy. I think it was really genuine and I think he's just a class guy. It shows that he's humble for him to go to someone and work on his craft and get better. It shows his approach to this game, he's just relentless, he just wants to be great.''
Kaepernick spent one day a week of study in a classroom setting, but on the field still spoke about concepts and ideas that came from the chalkboard study for ''constant mental work.''
In his second full season as a starter, the 27-year-old Kaepernick completed 289 of 478 passes for a career-best 3,369 yards and 19 touchdowns while throwing 10 interceptions and taking a career-high 52 sacks.
''I feel like there's been quite a bit of change,'' Kaepernick said. ''Obviously noticeable. Vernon said something to me right away when we started throwing. I just want to do everything I can to make sure I'm getting better and doing my part to help this team win. My knowledge picked up, not just mechanics-wise but mentally as far as the approach to the game.''
New Niners coach Jim Tomsula can't wait to get his first glimpse this spring.
''I'm fired up to watch him,'' Tomsula said. ''Obviously I admire the heck out of it. We didn't go out to fix something that was broke. He took good and made it better.''
Davis didn't attend the voluntary offseason program last year, but has changed his stance this spring. He and veteran safety Antoine Bethea each referenced the surprising retirement of five-time All Pro Patrick Willis affecting them and wanting to make every season - and every snap - count.
''I want to get better, I want to win, I want to develop some chemistry among my teammates,'' Davis said. ''You just never know when this game is over for you. Patrick Willis put everything in perspective for a lot of guys around here with him retiring.''
With all-time franchise rushing leader Frank Gore gone to the Colts, Kaepernick said ''it's going to be difficult without Frank,'' but he is confident going forward handing the ball off to second-year pro Carlos Hyde, a healthy Kendall Hunter and newcomer Reggie Bush.
Tomsula sure sounds encouraged, too, especially about the participation in the team's spring workouts.
''It's awesome,'' he said. ''Guys are awesome. Everybody's working. It's awesome. ... They're all millionaires. If I took a penny and threw it across the floor and said `whoever gets it is the champion,' they'd fight each other tooth and nail to get that penny. That's what they got.''
NOTES: LB NaVorro Bowman, who hasn't played following left knee surgery from a devastating injury in the January 2014 NFC championship game at Seattle, is expected to be on the field in some capacity when organized team activities begin. Tomsula also expects CB and 2014 first-round pick Jimmie Ward to be good to go following a second fracture and surgery on his right foot in eight months that prematurely ended his rookie season. ... DL Justin Smith won't be rushed into making a decision on his future and whether he retires or returns for a 15th season. ''The guy's played a lot of football, obviously near and dear to my heart,'' Tomsula said. ''I told him, go do his thing with his family. We'll get to it.''
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