Los Angeles Lakers star LeBron James was ruled out for Sunday's home game against the Denver Nuggets as he continues to deal with a thoracic muscle strain.

Though James won't play, Kyle Kuzma is available for the game. Kuzma hasn't been on the court since Dec. 8 because of a sprained left ankle and has been limited to 20 games this season.

James first sustained his injury, a pull in the rib cage area, against the Indiana Pacers on Tuesday and played through it during Thursday's loss to the Milwaukee Bucks. James didn't require an MRI, but this is a significant issue and not just a load management situation, sources told ESPN's Brian Windhorst.

Earlier this week, James said he didn't plan to miss any games this season for rest. James has also been dealing with a nagging groin issue recently, sources said. Last season a groin strain on Christmas Day derailed James and the Lakers' season.