James took a knee to the leg driving to the basket Friday against Philadelphia. He was down on the court for a couple of moments but remained in the game, scoring 31 points with 13 assists, both season highs.
James said after the game his leg was sore and he would get round-the-clock treatment in an effort to play Sunday.
James played in only two exhibition games after receiving an anti-inflammatory injection in his back. He said last month he hoped to play in all 82 regular-season games.
The Cavaliers have won five straight despite several key players being sidelined. Kyrie Irving (fractured left kneecap) had surgery in June and Iman Shumpert had wrist surgery in training camp. J.R. Smith has missed the last two games with knee and quad injuries.