The Ravens have placed running back Danny Woodhead on injured reserve and brought Jeremy Langford up from the practice squad to the 53-man roster.
Woodhead suffered a hamstring injury on the first series of the Ravens' regular-season opener in Cincinnati. On Wednesday, Head Coach John Harbaugh said he would miss at least four weeks, but it could be longer because hamstrings are unpredictable.
Moving him to injured reserve opens up a roster spot, but it also means Woodhead can't play for at least eight weeks.
He'll be eligible to return for the Ravens' Week 11 game in Green Bay, and can start practicing two weeks prior. After six weeks, the Ravens will have 21 days to either activate him or leave him on season-ending injured reserve.
Under this year's new league rules, teams can bring two players back from injured reserve. They do not have to designate who those players are ahead of time. Cornerback Maurice Canady (knee) is the Ravens' other logical candidate.
Woodhead caught three passes for 33 yards and added a 4-yard run during the Ravens' first series in Cincinnati, flashing his potential in Baltimore's offense. Now, as they have done a lot already due to a run of preseason injuries, the Ravens will have to turn elsewhere.
The Ravens signed Langford to the practice squad on Sept. 4, soon after he was released by the Chicago Bears during their cuts to 53.
Langford, 25, began last season as the Bears' starting running back, but suffered an ankle injury in Week 3, which opened the door for breakout rookie Jordan Howard. Langford never got the job back and finished with 200 rushing yards and four touchdowns and 142 receiving yards on 19 catches.
A fourth-round pick in 2014, Langford had his best season as a rookie, in which he ran for 537 yards and six touchdowns and caught 22 passes for 279 yards and a touchdown.
The 6-foot-0, 211-pound Michigan State product can be a dual-threat offensive weapon to complement Terrance West and Buck Allen, and give Baltimore necessary depth. Quarterback Joe Flacco and Head Coach John Harbaugh have also talked about the possibility of wide receiver Michael Campanaro filling in for Woodhead.
"It's an opportunity," Langford said. "I'm just coming to show the NFL what I can do and the Ravens what I can do."