San Francisco 49ers defensive lineman Justin Smith turns 33 in September. He's also on his second NFL team, having spent the first seven seasons of his career on the Cincinnati Bengals, including one as the team's franchise player.
So if there's anyone on the 49ers' roster with an understanding of the business side of the league, and how quickly an NFL roster can change as guys move on, it's him. And Smith is letting his teammates know just that Matt Maiocco of CSN Bay Area reported Thursday.
"The mindset that I've been spreading a little bit to the guys is, you know, your team isn't always stacked forever," Smith said. "With free agency (and) the way drafts are set up -- if you have successful seasons you get the lower end of the draft -- you have certain windows. You don't want to get into, 'Is this our window? Do we have two years, three years?' I wouldn't say that.
"I know with some of the guys we have and with free agency, we're not going to be able to keep this team together forever. Even age-wise, the whole team won't be the same."
The 49ers defense actually is in pretty good shape going forward. The average age of the 11 projected starters on defense is just 28 years, with three players -- Smith, Isaac Sopoaga and Carlos Rogers -- over the age of 30. Of the projected 11 starters, only Sopoaga and franchised safety Dashon Goldson are without contracts for the 2013 season.