The sixth-year pro had 55 yards on 10 carries before exiting the game and said afterwards he was due to get an MRI. Jennings, who signed a four-year contract with New York this offseason after four years with the Jacksonville Jaguars and one with the Oakland Raiders, has 91 carries for 396 yards and two touchdowns this season.
In Jennings's absence, rookie Andre Williams will likely get the bulk of the carries for the Giants. Williams, a fourth-round pick in this year's NFL draft, has 54 carries for 170 yards and two touchdowns this season.
Peyton Hillis becomes the team's top backup with Jennings out.
The Giants beat the Falcons 30-20 on Sunday and are 3-2 this season after winning three straight games. New York travels to play the Philadelphia Eagles this Sunday in Week 6.
- Ben Estes