SANTA CLARA, Calif. (AP) The theme emanating from the 49ers' headquarters amid their transition to a fourth coaching staff in four seasons is all about culture.
Only first-time head coach Kyle Shanahan isn't counting on his staff to dictate a winning attitude.
It's up to the players.
''Coaches can talk until they're blue in the face about what they want their standard to be, but that's all just coach talk and it's not really real until the players do that,'' Shanahan said at the start of the offseason program Monday.
''When the players hold each other accountable, when the players have a certain standard that they go to, whenever a guy is slacking, that the players get on that guy before the coach does, that's when you have something special.''
San Francisco's players, after one-and-done coach Chip Kelly was fired following last season's 2-14 finish, often spoke about the lack of accountability in the locker room.
Turning that around was the message Shanahan tried to impart when he spoke to the 49ers as a group Monday for the first time.
That kind of message is something the club's veterans are used to. Shanahan joins Jim Tomsula and Kelly as the third coach in as many seasons trying to turn things around after the team ''mutually parted'' with Jim Harbaugh after an 8-8 finish to 2014.
The team also fired general manager Trent Baalke, hiring John Lynch from the broadcast booth to run an organization for the first time.
''Things needed a change,'' five-time Pro Bowl tackle Joe Staley said. ''You look inwardly to what you control and what you as a player can do differently.
''And that's something that I challenged myself to do a lot more, and speak up when it's uncomfortable and getting more comfortable with being uncomfortable.''
The 49ers on Monday began the first phase of the offseason program, which includes weight training and conditioning on the practice field. Coaches can only work with players in the meeting room to go over the new playbook.
Coaches can get back out to the practice field during the first voluntary minicamp April 25, when All-Pro linebacker NaVorro Bowman expects to resume work after suffering an Achilles tear in early October.
''Well I did the running test today. I participated in everything,'' Bowman said. ''I'm feeling good, just trying to get out the last kinks and make sure I'm ready for minicamp coming up.''
Bowman suffered the injury to his left leg against the Cowboys in Week 4. His absence was the most notable for a defense that dealt with a long list of injuries before finishing ranked last in opponents' yardage and scoring. The defense allowed a franchise-worst 2,654 yards rushing.
Bowman said he began the rehab process slowly, but ramped it up in recent weeks. The injury came to his left leg, the same leg that caused him to miss all of 2014 after he tore his ACL and MCL in the NFC title game following the previous season in Seattle.
''The process has been great. There's been no setbacks. Just looking forward to getting back out there and showing what I have,'' Bowman said.
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