Johnson will have surgery to repair his dislocated wrist and will be placed on injured reserve, ESPN NFL Insider Adam Schefter reported on Tuesday. Johnson received a second opinion on the injury, which he suffered in the third quarter of Arizona's loss to the Detroit Lions on Sunday. He's expected to be out eight to 12 weeks, which could see him return anywhere from Week 9 in early November to Week 13 in early December.
In the meantime, the Cardinals still have games to play.
Though the team hasn't made any roster moves official as of Tuesday morning, there were reports that Arizona signed running back D.J. Foster off the Patriots' practice squad and will re-sign Chris Johnson, who they cut Sept. 2, a source confirmed to ESPN on Tuesday. On Monday, Cardinals coach Bruce Arians said signing Johnson was an "option."
Here's a look at the Cardinals' updated depth chart at running back:
Chris Johnson: Johnson is re-signing with the Cardinals, and he will likely leap to the top of the depth chart, where he sat two years ago before he suffered a fractured tibia in Week 12. Johnson, 31, had fumbling issues during the preseason, which led to him being cut. But Johnson is the most qualified of Arizona's running backs to handle the heavy workload of being an every-down back working between the tackles. He may not be the explosive back that David Johnson is, but Chris Johnson is capable of getting 100 yards per game on 20 or more carries. The biggest question this season will be his durability. He ended the past two seasons on injured reserve after not missing a game because of injury in his first seven seasons.
Kerwynn Williams: It looked like the shifty speedster would relinquish his return duties and become the Cardinals' starting running back after David Johnson's injury, but that may change depending on Chris Johnson's status. Williams has never started a game in five seasons but likely would have been used as Arizona's primary rushing option. He's small -- just 5-foot-8 and 198 pounds -- but can take a pounding between the tackles. He had 111 of his 157 rushing yards last season outside of both tackles, so his speed can be a factor.
Andre Ellington: He hasn't started a game since Week 6 of the 2015 season. Since then, Ellington has just 460 total yards -- 246 rushing and 214 receiving -- on 89 tackles. Once Chris Johnson took over for him and hit a stride in 2015, en route to becoming the NFL's third leading rusher before his injury that season, Ellington was relegated to the bench. He has an injury history to account for, as well. He lost the starting job in 2015 after suffering a knee injury early in the season and never regained it. He's also suffered from injuries to his foot, hip flexor and knee during his career. Ellington is the closest option the Cardinals have to David Johnson in the passing game. He has a quickness and acceleration out of the backfield in open space that exceeds Johnson's. Ellington has 854 career receiving yards but only 120 over the past two seasons.
Eli Penny: He spent his rookie season in 2016 on the Cardinals' practice squad. He's a big, bruising back at 6-2 and 234 pounds. He lined up at fullback for his only offensive snap on Sunday in Detroit. Penny impressed during training camp, which helped him make the 53-man roster.
Foster: He was reportedly signed by Arizona off the Patriots' practice squad, according to multiple ESPN reporters. He played in just three games last season while bouncing between the active roster and the practice squad. He's a versatile back, with pass-catching ability to complement his rushing skills. He had seven carries last season for 24 yards and one catch for two yards. He can also be an option in the return game. He had one kickoff return for 30 yards last season.