The plan is for Swift, who missed last week's game against Seattle with shoulder and ankle injuries, to return after the bye (Week 7), barring unforeseen development, the source said.
He did not practice Wednesday or Thursday.
Swift got off to a hot start in the first two games of the 2022 season, becoming the first Lions player since Barry Sanders in 1997 to go back-to-back games in producing a 50-plus-yard rush.
He has 231 rushing yards on 27 attempts, averaging a career-best 8.6 yards per carry in three games.
Without Swift, the Lions will continue to rely on Jamaal Williams as the featured back. He leads the league with six rushing touchdowns, which is a franchise-best through four games played. Williams, in his sixth season, told ESPN that he feels he's playing the best football of his career and that he believes his body is sustainable to maintain the offensive production.
"Yeah, most definitely. I've always been like this. I've always been training myself to just be able to handle these types of workloads and type of seasons, so I've always had the mindset for it," Williams told ESPN. "I'm just grateful to have a great offensive coordinator, offensive coaches, linemen and players to play with who are putting me in positions to make great plays."
When Swift is able to return, coach Dan Campbell said they'll be particular on what plays they're giving him to watch his workload so he won't be as exposed to injury.
ESPN's Eric Woodyard contributed to this report.