SANTA CLARA -- Blake Costanzo had been keeping busy re-tiling his bathroom back home in New Jersey and doing regular yard work.
He remained optimistic he would land himself a job, even as free agency lingered into its fourth month.
The linebacker and special teams standout rejoined the 49ers on Tuesday, signing 2½ years after leaving the organization to play for the Chicago Bears. He signed a one-year contract for the veteran minimum of $855,000 for players with seven to nine years of experience.
"The biggest thing is this stadium right behind here," Costanzo said of what has changed, looking toward $1.2 billion Levi's Stadium. "There are a lot of new faces, but there are also a lot of guys I played with. It's a good opportunity to come out here and play some football again. I was doing too much yard work at home."
The 30-year-old Costanzo played 16 games for Chicago last season and finished with nine tackles and a forced fumble while also contributing on special teams.
After flying cross country Monday, Costanzo participated in Tuesday's organized team activity, and was one of the last players to return to the locker room after a session in the weight room. He said he spoke to a couple of other teams, but "the timing was right here."
"This was a good opportunity for me to come here, compete and maybe help some younger guys they have on the roster," Costanzo said. "My only competition is myself. I'm going to try to find a way, whatever it may be."
Costanzo is also learning some new aspects of the playbook from special teams coach Brad Seely, who also coached him in Cleveland and brought him to the Bay Area for the turnaround 2011 season, coach Jim Harbaugh's first year.
"Blake was here with us a few years ago. He's a great guy -- a guy who comes to work every day and a great team player," linebacker Patrick Willis said. "The guy is going to go out there on game day -- or even practice -- and gives it everything he's got. We're very fortunate to have a guy like that on our special teams. We lost some guys who had been some key special teams players for us, so to add Blake back is really going to help us out big time."
San Francisco will count on the depth at linebacker that Costanzo helps provide given All-Pro NaVorro Bowman is recovering from a left knee injury sustained in the NFC championship game. Bowman could miss at least half the season.
In addition, linebacker Aldon Smith might face a multiple-game suspension from the NFL for his off-field legal issues over the past two years.
Last month, Smith pleaded no contest to three felony weapons charges and two misdemeanor counts of driving under the influence. He faces a sentence ranging from spending no time in custody to a maximum of four years and four months in jail. Smith is scheduled to be sentenced July 25, two days after the 49ers open training camp in Santa Clara. He left the facility Tuesday offering a thumbs-up.
"For us, it's not something we worry about. He's out here working. He's practicing every day," Willis said. "He's working out every day. He's been a great teammate. That's our focus right now: worrying about the present. When that time comes, whatever is decided, that's what it will be. We'll have to get better as a football team. If he's not out there, then as with last year, some of the guys will have to step into his place and play big time."
Nose tackle Ian Williams believes he will be full strength or close to it by the start of training camp next month. A first-year starter, Williams' 2013 season ended with a broken leg and torn ligaments in his left ankle in Week 2 at Seattle. He has had four surgeries since, the most recent in February to have a metal plate removed.
"It took a lot out of me," Williams said. "Things happen for a reason. I'm back, though, I'm back."
NOTES: The Sacramento Bee reported Tuesday the 49ers are scheduled to meet with quarterback Colin Kaepernick's agent this week to discuss a long-term extension. ... Not on the field during team drills Tuesday: WRs Stevie Johnson, Michael Crabtree and Anquan Boldin, TE Vernon Davis and RG Alex Boone. The team's mandatory minicamp is June 17-19. ... New T Jonathan Martin worked out on the side and in the weight room as he recovers from mononucleosis. ... The Niners waived guard Al Netter on Tuesday.