SANTA CLARA When the NFL free-agency period begins Tuesday, the 49ers' biggest move is expected to be one of subtraction.
Beginning at 1 p.m., the team can trade quarterback Alex Smith to Kansas City, a transaction that was agreed to two weeks ago. The 49ers will do that quickly to free $9.75 million in salary-cap space.
That, in addition to last week's release of kicker David Akers, will give the 49ers more than $12 million of salary-cap cushion for free agency.
The team believes the best method for sustaining its recent success is through the draft, and many of the current holes on the roster will be filled with incoming rookies.
Last year, however, the 49ers augmented that approach with a few modestly priced free agents wide receivers Randy Moss and Mario Manningham, for instance and they're likely to do the same this month.
The defensive front seems to be a prime target.
The 49ers already met with two veteran players who were released in recent weeks, Cullen Jenkins and John Abraham. Jenkins agreed to a three-year deal with the New York Giants on Sunday.
Abraham, who has played defensive end, is being eyed as an outside linebacker in the 49ers' three linemen/four linebackers scheme.
The 49ers' interest appears to be an acknowledgment they must have a better and deeper defensive front in 2013. Starters Aldon Smith, Justin Smith, Ahmad Brooks and Ray McDonald all played more than 90 percent of the team's defensive snaps in 2012, and the pass rush dwindled as the season wore on. Through Week 14, the 49ers had 35 sacks, an average of 2.5 per game. After that, they averaged 1.4 sacks.
The defensive line also is an area of need because the 49ers could lose two of their own free agents, starting nose tackle Isaac Sopoaga and top backup Ricky Jean Francois.
Agents for both players say they have received inquiries from multiple teams in the past few days. Jean Francois is being looked at by five teams, including the Philadelphia Eagles, and he likely will make visits this week.
Teams that run a 3-4 defense and are in need of a sturdy nose tackle are interested in Sopoaga, who is 31 but who has been lightly used the past two seasons in a 49ers defense that removes its nose tackle in passing situations.
Other areas of need for the 49ers:
Safety Fresh off a season in which he made the Pro Bowl and the All-Pro team, Dashon Goldson will be the top safety on the market. The question is whether other teams will be willing to meet his asking price.
Goldson is believed to be seeking $8 million per year, similar to what San Diego safety Eric Weddle received two years ago. The market, however, may have contracted. Atlanta safety William Moore, for instance, recently signed a deal with the Falcons that averages about $6 million a year.
If, for the second time in three seasons, Goldson doesn't get the offers he feels he deserves on the open market, he could be back with the 49ers.
Receiver The 49ers are expected to let pending free agents Moss and return man Ted Ginn go, and Manningham and Kyle Williams are coming off serious knee injuries.
The 49ers have shown early interest in Browns returner/receiver Josh Cribbs, who played under 49ers special-teams coordinator Brad Seely for two seasons in Cleveland.
Cribbs would solve the 49ers' issue at punt returner, and after catching only seven passes last year, he is seeking a bigger role on offense.
Quarterback The 49ers could look to Cleveland to fill the need there, too.
The Browns are not expected to put up a big fight to keep Josh Johnson, whom they acquired in late December. Johnson, of course, spent the 2012 offseason with the 49ers and is a more athletic and bigger-armed alternative to Scott Tolzien, who beat out Johnson for the No. 3 role before last season.