Nutt did not say what the violations were, but said the suspensions could also include the season finale against Mississippi State.
Ole Miss announced Nutt would not return as coach next season on Nov. 7 after the Rebels lost their 12th straight SEC game. He is coaching the remainder of the season.
"I hate it," Nutt said Tuesday. They've "got to learn how to handle change and it's tough for a lot of them, especially when a season doesn't go just right it's easy to let go. These last few weeks you try to teach them the best you can that life can be hard and lessons are tough, but there's no easy way out. There are no shortcuts, you know?
"You finish and do right. That's the bottom line."
Mackey has started the past six games and thrown for 1,112 yards, seven touchdowns and five interceptions this season. Backup Zack Stoudt, who would be the likely starter against the Tigers, has thrown for 542 yards, two touchdowns and seven interceptions.
Scott has rushed for 529 yards and six touchdowns this season. Rarely-used running back Korvic Neat was also suspended.
It's the second time Mackey has been suspended this season. He missed the season-opener against BYU after he was arrested and charged with disorderly conduct after allegedly being involved in a fight at a downtown Oxford bar.
After it was announced that Nutt would resign, the fourth-year Ole Miss coach said he didn't expect to have any discipline problems. But now the already outmanned Rebels will face top-ranked LSU without two of their best offensive players.