EAST RUTHERFORD, N.J. -- New York Giants running back Brandon Jacobs has a sprained medial collateral ligament, a source told ESPN NFL Insider Adam Schefter, and the injury could keep him out of Sunday's game against the Seattle Seahawks.
The injury is considered to be a mild sprain, a source told ESPNNewYork.com's Ohm Youngmisuk on Friday, but Jacobs did not practice and was listed as doubtful.
"I thought he would [make more progress], but that hasn't been the case," coach Tom Coughlin said. "I don't know if it's a setback, but there is some swelling that has not subsided."
Jacobs said he suffered the MCL sprain against the Cardinals, but he did not know exactly when the injury occurred. It was first characterized as "knee swelling."
Asked specifically Thursday about his status for Sunday's game, Jacobs replied, "I don't really know what they're thinking as far as that. You gotta speak to Coach Coughlin about that. ... It doesn't really matter what I'm thinking.
"It doesn't feel too bad. I'm waiting to be unleashed. That's it."
The 29-year-old Jacobs has rushed 38 times for 116 yards and two touchdowns through the first quarter of the 2011 season. The Giants are 3-1 and tied with the Redskins atop the NFC East.
Jacobs underwent surgery in 2009 to repair a torn meniscus in his left knee, but Jacobs indicated Thursday that the "swelling" -- which later became a sprain -- was in his right knee.
If Jacobs is unable to go, starter Ahmad Bradshaw should see the bulk of the workload against Seattle. Bradshaw has rushed 55 times this season for 228 yards and two touchdowns.
Reserve D.J. Ware and rookie Da'Rel Scott could get some of the carries as well.
"It's an opportunity for someone else to step up," Coughlin said.
ESPNNewYork.com's Mike Mazzeo contributed to this report.