The 49ers on Monday morning agreed with defensive lineman Arik Armstead on a lucrative five-year contract extension just as the NFL's open-negotiating period began for scheduled free agents.
The negotiations have been completed, but the agreement has not officially been signed by all parties, according to a source.
The agremeent, which took shape Sunday and Monday morning, means the 49ers did not have to use the franchise tag at a cost $17.788 million for the 2020 season to retain Armstead. The deadline to use the franchise tag passed at 8:59:59 a.m. PT without the 49ers tagging Armstead.
That decision to leave Armstead unprotected foreshadowed an agreement for the 49ers to keep Armstead with the organization beyond the upcoming season.
Armstead now is signed through the 2024 season with a deal that could pay him up to $85 million -- an average of $17 million annually -- over the life of the contract, according to a source.
Before the completiion of the contract, the 49ers were less than $11 million under the cap, according to OverTheCap.com, and would have to clear space to fit Armstead's deal at the start of the new league year on Wednesday, 1 p.m. if he were the franchise player. Armstead was scheduled to be an unrestricted free agent.
On Sunday, after the players voted to approve the new collective bargaining agreement, the league set the 2020 salary cap at $198.2 million per team.
The 49ers and Armstead's representation continued to work through the weekend and Monday morning on a deal that would count far less against the 2020 cap than the franchise figure.
At the end of the season, Armstead said he was open to the possibility of the 49ers tagging him as their franchise player. The 49ers avoided that last-resort scenario by working out a deal with Armstead.
"I'm from Northern California," Armstead said. "I would love to be here and continue my career here. I feel like we have a special team that I want to be a part of and try to get back to the Super Bowl."
Armstead, 26, a five-year veteran, had his best NFL season in 2019. He continued to be a solid force against the run in base situations, then moved inside to rush the passer. Armstead had nine sacks in his first four season.
Last year, he registered a team-leading 10 sacks in the regular season and added two more in the postseason.
Armstead was one of five first-round draft picks on the 49ers' defensive line last season. He was the No. 17 overall pick in 2015. DeForest Buckner, Solomon Thomas and Nick Bosa were also first-round picks of the 49ers, while Ford was a first-round selection of the Kansas City Chiefs.