McGill injured his left ankle against Georgia Tech.
"There is no certainty he will be ready this week," Bunting said during Tuesday's press conference.
Senior Jacque Lewis made his first start of the season against Louisville, but strained his left shoulder in the third quarter and did not return. Against FSU, Lewis ran for 67 yards on 13 carries and caught a 31-yard pass from Durant.
Bunting remarked that last week's practice prior to the Tar Heels' trip to Tallahassee was their best of the season. He also projected an optimistic outlook to this week's preparation for N.C. State.
"I'm really pleased with the way the team responded yesterday," he said. "We just need to keep moving forward. I was able to show them so many plays where they were successful [versus FSU]. We feel like we got a little bit better.
"[The rush defense] is still average. We understand a little bit better where we're supposed to be. We're not getting knocked off the ball like we used to."
Perhaps the Tar Heels biggest concern will be stopping the ACC's leading rusher T.A. McLendon, who is averaging just slightly more yards per game (108.7) than Georgia Tech's P.J. Daniels (108.0).
Bunting likened McLendon to former Green Bay Packers fullback Jim Taylor, because of his ability to run over defenders. However, Bunting went on to note McLendon's speed and ability to "take it down the boundary."
"He is a Rockem Sockem Robot," Bunting said referring to the 1970s era children's toy. "He knocks the heads off. When he's on the field, he makes things happen. He's a really good, physical player.
"They're doing a great job with all their players, but particularly, they're getting their run game going."
Bunting said he expects there to be a little extra spirit in practice this week.
"I know and feel the fans' desires along with the team's desires," Bunting said. "It's exciting."
While slowing McLendon will be an emphasis, getting off to a quick start could be of equal importance. The Tar Heels have yet to score first in their five games this season. To make matters worse, they've given up points on each of their opponents opening drives. For a young defense that proved it could thrive on confidence during the win over Georgia Tech, scoring first and/or keeping the Wolfpack off of the scoreboard early could be a major key to the contest's outcome.
"That sounds like Carol Vermeil," Bunting said referring to the wife of his NFL coaching mentor Dick Vermeil. "‘Will you ever stop them on the first drive?' she would say."
Finally, with plenty of recruiting prospects for both teams expected to be in attendance, Bunting admits this game takes on even more significance.
"We've been recruiting really well within this state," he said. "It's important for us to get this state under control. Four of five times a year, we go head-to-head [with N.C. State] for the same guy."