The Detroit Lions and former Chicago Bears running back David Montgomery reached an agreement on a three-year, $18 million deal, including $11 million guaranteed, a source told ESPN's Adam Schefter on Tuesday.

With Montgomery departing, the Bears signed former Seattle Seahawks running back Travis Homer to a two-year deal worth a maximum of $4.5 million, according to his agent, Spencer Cannold.

Montgomery, 25, joins a Lions running back corps that scored a league-leading 23 rushing touchdowns last season, including a league-best 17 by Jamaal Williams and five by D'Andre Swift. Williams enters this offseason as an unrestricted free agent while Swift remains under contract through 2023, on the last year of his rookie deal.

In a loaded class of free agent running backs, Montgomery had the 10th-most rushing yards (801) and was fifth in receiving (316) yards of those players. He generated his highest yards per catch (9.3) in 2022 and recorded his first receiving touchdown since his second season in Chicago.

Montgomery was drafted by former Bears general manager Ryan Pace with the 73rd overall pick in the third round of the 2019 NFL draft. In four seasons with Chicago, Montgomery totaled 3,609 rushing yards and 26 touchdowns along with 1,240 receiving yards and four TD receptions.

From 2019 to 2021, Montgomery led the Bears in rushing and posted a career-best 1,070 rushing yards in 2020 when an injury to former Chicago running back Tarik Cohen allowed Montgomery to emerge as the team's top rusher.

Perhaps his biggest on-field attribute is his ability to stay healthy while playing a position notoriously associated with injury. In four seasons, Montgomery appeared in 60 games and only missed six due to injury. In 2022, the running back sustained ankle and knee injuries during a Week 3 win over the Houston Texans and only missed one game as a result.

At the conclusion of the 2022 season, Bears general manager Ryan Poles praised Montgomery for his contributions on the field and leadership that helped insulate the locker room during a 3-14 season.

Homer, a sixth-round pick of the Seahawks in 2019, has seen limited time on the field, totaling 453 yards and a touchdown on 83 carries across four seasons.

ESPN's Courtney Cronin contributed to this report.