The Chicago Bears are giving Buffalo Bills free agent linebacker Tremaine Edmunds a four-year, $72 million contract that includes $50 million guaranteed, a source told ESPN's Adam Schefter.

It is the largest four-year contract for an inside linebacker in the NFL.

Edmunds is the second starting linebacker added by the Bears on Monday. Earlier in the day, the Bears agreed to a three-year contract with Philadelphia Eagles free-agent T.J. Edwards worth $19.5 million, including $12 million in guaranteed money, a source told ESPN's Courtney Cronin.

The Bears also made a move to bolster their offensive line, agreeing to a three-year contract with Tennessee Titans free agent guard Nate Davis, a source told ESPN, confirming a report by NFL Network.

Over Edmunds' five years with the Bills, the linebacker has developed into one of the defense's leaders and key players. He has been a starter from the jump, starting all 74 regular season games and eight postseason games he has played.

The 16th overall selection in the 2018 NFL draft out of Virginia Tech -- after the Bills traded up to select quarterback Josh Allen at No. 7 -- Edmunds will turn just 25 years old in May despite already playing five NFL seasons.

The two-time Pro Bowl selection has had 100-plus tackles every season he has played. Bills defensive coordinator Leslie Frazier has spoken about wanting to see Edmunds make more splash plays. Edmunds has 5 career interceptions, 35 passes defended, 2 forced fumbles and 6.5 sacks.

Edmunds has improved in pass coverage, with his route awareness and ability to get to depth as a zone defender. He's a long, 6-foot-5 linebacker with downhill acceleration against the run and second-level range to track the ball.

In 2022, he played in 13 games, missing time with injuries, but coach Sean McDermott was impressed by the season he put together, calling it "his best year" and noting how he grew as a leader and in his performance.

Edmunds has been responsible for distributing the playcalls on the defensive side of the ball and was named a defensive captain each of the last four seasons.

Davis, 26, started 54 games at right guard for the Titans over the last four seasons, including 12 starts in 2022 before an ankle injury landed him on injured reserve in December. His pass block win rate of 93.2% was the highest among Tennessee's offensive linemen, while he finished with a run block win rate of 68.8%.

Davis, who made his first career start in Week 5 of his rookie season after being selected in the third round of the 2019 draft, can reach block or climb in zone-run schemes, and he can set an anchor to take on power rushers in pass protection.

He started all 16 games in his second season, helping pave the way for Derrick Henry to become the eighth running back in NFL history to rush for 2,000 or more yards. He returned in 2021 to start 14 games at right guard as the Titans finished with a 12-5 record and the top seed in the AFC.

ESPN's Alaina Getzenberg, Turron Davenport and Matt Bowen contributed to this report.