Los Angeles Lakers forward LeBron James was ejected from Sunday's 121-116 win over the Detroit Pistons for an errant swinging arm that drew significant blood from the face of Isaiah Stewart, the NBA said.

The incident took place with 9:18 remaining in the third quarter, with the Lakers trailing 78-66, as James swung his arm through and struck Pistons center Stewart in the eye area when battling for a rebound after a free throw.

Stewart, with blood streaming from his eye, had to be held back by multiple staff members as he attempted to confront James on several occasions.

Following an official review, James was assessed a 'Flagrant two penalty', resulting in his ejection for the second time in his 19-year career. His first ejection came in November 2017 against the Miami Heat.

Stewart was also ejected, while Lakers guard Russell Westbrook was handed a technical foul for his involvement in the scrap following the incident.

Pistons head coach Dwane Casey said Stewart received eight stitches and hoped the center would be spared a possible suspension.

"He shouldn't be facing anything," Casey said. "Not getting off the court in time? The league will have to decide that.

"But the man got eight stitches, whatever it is, across his forehead. He was upset. Blood running down his face. I don't see any ramifications from the league from that standpoint."

Lakers forward Anthony Davis defended James, saying the collision wasn't intentional.

"Everyone in the league knows LeBron is not a dirty guy," Davis said, adding that James was attempting to apologise to Stewart immediately after the foul before things kicked off.

"We're not promoting violence. I'm not promoting violence."

After trailing in the third quarter, the Lakers bounced back in the fourth quarter to seal a win in Detroit and end their three-game losing streak.