Pericard, who only joined The Lions on loan last week, was stretchered off late in the second half after going for the ball and could be out of the game for up to six months.
"He'll be out for the rest of the season and will go back to his club," said Jackett. "It's so heartbreaking for the lad."
The 26-year-old will return to Stoke City, leaving Jackett pondering his options for the remainder of the season.