GREEN BAY, Wis. -- The Green Bay Packers have lost one of their core special-teams players, backup linebacker Andy Mulumba, to a knee injury, but starting safety Micah Hyde appears to have avoided a major injury.

Both were injured in Sunday's win over the New York Jets.

Hyde, who was injured at the end of a second-quarter punt return, said Monday that he has some swelling in his left knee but believes it was just a bruise.

"I just took a little shot on the knee cap, nothing serious," he said. "Nothing major. Just a little soreness."

However, Mulumba was not as fortunate. He was injured while covering a punt in the fourth quarter and sustained what coach Mike McCarthy called a "significant" injury. That's usually code for a torn ACL, although McCarthy declined to give specifics.

"It didn't look good during the game, and it doesn't sound very good," McCarthy said.

The most puzzling injury situation, however, was to cornerback Casey Hayward. He did not play at all on defense after playing 36 of 70 snaps in Week 1.

Against the Jets, the Packers used Davon House as their No. 3 cornerback, which was in the plans all along. However, Hayward also did not play in the dime (Jarrett Bush got that call) and defensive coordinator Dom Capers said Hayward may have been dealing with a hamstring injury -- the same injury that limited him to three games last season. Yet Hayward still managed to play 11 special-teams snaps.

McCarthy said Hayward was checked out by the team’s medical staff on Monday but did not have any update. The team does not have to file an injury report for this week's game at the Detroit Lions until Wednesday.