When Chris Carson left Seattle last January following the Seahawks’ playoff loss to the Rams, he headed into the unknown.

“It was definitely a possibility I was done with Seattle,’’ Carson said Thursday when he talked via Zoom to reporters.

Indeed, Carson spent the 2020 season — the last on his initial four-year rookie contract — unsure what the future held.

Carson was still unsigned when the free agency signing period began on March 17. And he was still unsigned two days later after the Seahawks and other teams around the league had made major moves.

“Stressful,’’ Carson said candidly of the process, which was his first journey into free agency and one he hoped could help set he and his family up for life.

Adding to it was the challenging nature of free agency in 2021, with teams having $15.7 million less in salary cap space, and also the ever-changing views around the league on the value of running backs.

But finally the calls started to come, not just from the Seahawks but also from a few other teams around the league, reportedly including the New York Jets, New England Patriots and Carolina Panthers.

The decision, Carson said, “was definitely difficult. … Teams made offers. Some teams made it tough to decide to sign with the Seahawks.’’

But Seattle’s offer — essentially a two-year deal worth up to $10.4 million with $5.5 million guaranteed (it includes a voidable third year) — finally proved enough to keep Carson around.

“It was the team that gave me my first shot in the league,’’ Carson said. “So it felt like it was the right decision.’’

The contract means Carson will be a free agent again following the 2022 season when he will be 28 years old, potentially in a position to cash in big again.