Denver spent a good chunk of Monday adding offensive pieces to its roster.

It also found time to retain one of its core defensive players.

The Broncos agreed to a three-year contract with linebacker Alex Singleton, the team’s leading tackler in 2022, getting him back in the building and ensuring that his status as a free agent lasted only a matter of hours.

Singleton’s deal is worth up to $18 million and comes with $9 million guaranteed, a source confirmed to The Post.

Singleton told the Post on Monday evening, “Man, I am beyond happy. It’s where I wanted to be. Happy to get a deal done and be back home. A lot less stressful and I’m just beyond happy.”

The California native arrived in Denver a year ago on a one-year, minimum salary deal but established himself quickly as a viable option at linebacker and core special teams player, too. Both Josey Jewell (four games) and Jonas Griffith (foot) missed time over the course of the season, and Singleton turned himself into a virtually every-down player. He finished the season with 163 tackles, most by a Denver defender since 2007.

At the NFL Combine, general manager George Paton said the franchise would “love” to get Singleton back in the fold.

“He’s just a baller,” Paton said. “We signed him to be a really good special teamer, compete for the starting job. And he didn’t even start to start the year. Then he just took off. He’s just a football player. We’d love to have Alex back. He’s a great leader, has a nose for the ball. Players gravitate towards him.”

So, too, did the Broncos. Now Singleton will be around — and in the middle of the Denver defense — for the coming years.

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