Faced with the prospect of losing their top two nose tackles, the 49ers gave a two-year contract Monday to reserve Ian Williams, who was inactive for all but three games last season.
Starting nose tackle Isaac Sopoaga and versatile lineman Ricky Jean Francois are both slated to become unrestrictred free agents Tuesday at 1 p.m.
Williams' $3.2 million extension includes $2 million guaranteed, with a $1 million signing bonus, according to a league source.
Williams made the 49ers roster in 2011 as an undrafted free agent out of Notre Dame, and he said Monday that this contract extension represents his first career signing bonus.
"I came with a suitcase and some dreams," Williams said. "I was able to call my mom and hear her excitement over the phone and know I have a little more stability now. But it's the tip of the iceberg and I'm willing to dig even deeper to get where I need to be."
He appeared in one game as a rookie, and he tallied six tackles in three games last season.
Asked if he's capable of starting, Williams humble and said he's merely going to "compete" and "do what I need to do."
"We are very pleased to extend the contract of a young, talented player like Ian," general manager Trent Baalke said in a statement. "He will have the opportunity to continue to grow in our defense, and we look forward to his future development. Paraag and Drew deserve credit for working hard to put this deal together."
That would be Paraag Marathe, the 49ers' chief operating officer and primary contract negotiator, and Drew Rosenhaus, Williams' agent.
"It's a blessing to know how much I mean to the team and how far I've come since I got here," Williams said.
Going undrafted out of Notre Dame is "still burning in my mind and heart" to prove his worth, and he called it a "blessing in disguise" to end up with the 49ers' strong unit and a father figure for a position coach in Jim Tomsula.
"Watching Ricky and Ice at my position got me ready for the workload I'll partake in the next few seasons," Williams added.
Of Williams' three cameos last season, he appeared in 12 snaps during the 49ers' 42-13 loss at Seattle on Dec. 23. Williams left no doubt how intense things are becoming between the NFC West front runners.
"They've become a huge rival," said Williams, noting that he's enjoyed friendly trash talk with a fellow Notre Dame product on the Seahawks -- wide receiver Golden Tate.
The Seahawks are poised to cause more havoc for Williams and the 49ers defense, having reportedly come to terms Monday on a trade for Minnesota Vikings wide receiver Percy Harvin.