Jefferson has been struggling with right knee inflammation for the last month and had it drained three times in the last two weeks. He's tried to play through the pain, and this was the first game he has missed during that span.
He did not play in the second half of Charlotte's loss Friday night at Indiana because of knee soreness.
Clifford says it's too soon to know if Jefferson will play again this season.
The Hornets kept their slim playoff hopes alive, with the win pulling them within 1½ games of Boston for eighth place in the Eastern Conference standings.
The Associated Press contributed to this report.