Green Bay Packers head coach Mike McCarthy has revealed that safety Morgan Burnett and linebacker Brad Jones are struggling with injuries ahead of their season opener.

The duo sustained the injuries during practice and are now in a fitness race to be ready for their clash with the San Francisco 49ers on Sunday.

McCarthy told reporters: "Morgan Burnett and Brad Jones both came into today with some hamstring soreness. They both had their hamstrings injured, so we'll see how it goes.

"We'll be smart with those guys. Forty-eight hours, it's important to get those guys ready to play the game. Hopefully, it's nothing more than that."

Wide receiver Jordy Nelson is expected to be fit for the game on Sunday.