Christian McCaffrey injury still a cause for concern for 49ers ahead of season opener with Jets

Christian McCaffrey returned to practice this week after missing the entirety of preseason with a calf injury.

But that issue is clearly still an issue of some concern for the San Francisco 49ers' star running back going into their season opener with the New York Jets on Monday.

Niners head coach Kyle Shanahan confirmed in his press conference ahead of Thursday's practice that McCaffrey would be limited with what is officially listed as a calf/Achilles injury.

The word Achilles will likely lead to worry among some fans, but Shanahan said there is no new injury for the reigning Offensive Player of the Year.

49ers' Injury Report

DNP: DL Yetur Gross Matos (knee), LB Dee Winters (ankle)

Limited: RB Christian McCaffrey (calf/Achilles), RB Isaac Guerendo (groin), WR Jauan Jennings (ankle), S Talanoa Hufanga (knee), OL Aaron Banks (finger)

There is no suggestion McCaffrey is in danger of missing the primetime encounter but, with rookie fourth-rounder Guerendo nursing a groin issue, the 49ers' situation at running back is something to monitor.

On the defensive line, Gross-Matos' participation looks in some doubt as he continues to recover from the knee sprain he suffered in the preseason finale last month. With linebacker Winters missing practice because of his ankle injury, veteran backup Demetrius Flannigan-Fowles would appear to be the frontrunner to start at SAM linebacker on base downs.

Shanahan, meanwhile, said All-Pro safety Hufanga has "a possibility" to make his long-awaited return from the torn ACL he suffered in November last year.

If Hufanga is not able to play, then George Odum or rookie Malik Mustapha will start at safety next to Ji'Ayir Brown.