Around the NFC West: 49ers' surreal day

Isaac Sopoaga had been with the San Francisco 49ers continuously since 2004, when Dennis Erickson was head coach.

Around the NFC West: March 13, 2013

Alex Smith (2005) and Delanie Walker (2006) came to the team during Mike Nolan's tenure.

All three left the 49ers shortly after the 2013 free-agent signing period opened Tuesday.

Another San Francisco mainstay, Dashon Goldson, was visiting with the Tampa Bay Buccaneers and all but certain to join Sopoaga, Smith and Walker as former longtime 49ers.

It's a little surreal when a team we've come to know so well remakes itself to such a degree all at once. Sopoaga, Smith and Walker combined to play in 304 regular-season games as 49ers. Goldson played in another 81. That's a lot of institutional knowledge heading out the door.

The 49ers are going to be Colin Kaepernick's team for the foreseeable future, fresh and new. The transformation felt expedited Tuesday.

Additional changes are on the way as San Francisco approaches the draft with more choices than any other team possesses. A year from now, we could realistically be discussing Justin Smith's future beyond his contract, which runs through 2013. Frank Gore, who turns 30 in May, isn't going to stay forever, either.

It's a lot to consider just five weeks after the 49ers appeared in the Super Bowl.