Frazier, a 6-foot-1 point guard, ripped away a defensive rebound from the 6-foot-11 Drummond underneath the Pelicans' basket with 1:23 to play in the third quarter. Drummond then grabbed Frazier's left arm and tried to wrap him up around the waist, leading to a personal foul call.
As they jostled for position, Frazier tried to forcefully break away, and Drummond responded by shoving Frazier in the back of the guard's head with his right arm. Players from both teams had to separate Drummond from Frazier and Pelicans star Anthony Davis.
After an official replay, Drummond was assessed a flagrant foul 2 and automatically ejected.
"We lost the game," Drummond said. "One thing led to another, I was in the locker room. They won the game. Simple as that."
Drummond finished the game with 13 points and 17 rebounds -- 10 of which came on the offensive glass.
"We lose our composure last night and get a technical that [almost] cost us the game, and then tonight he loses his composure," Pistons coach Stan Van Gundy said, referring to Kentavious Caldwell-Pope's technical with 10.8 seconds left in the Pistons' 120-113 victory over the Portland Trail Blazers. "Yeah, it's ridiculous."
Frazier made one of his two allotted free throws and scored twice more from the field before the end of the quarter for his only points of the game.
"I'm not going to back down from anybody," Frazier said. "That's how I was raised, and I had to fight for a lot of where I am to be successful. So I'm not going to back down from anybody. I let the refs handle it. They were able to get it on film to see what happened. Then [I] moved on from it. "
The Pistons, at 29-32, are a game ahead of the Miami Heat for the eighth seed in the Eastern Conference.
New Orleans, at 24-27, is four games back of eighth place in the West.
"He's a little hothead," Davis said of Frazier, "so you have to make sure that we don't lose him. Because he comes in and plays well for us, off that bench running that second unit. We're definitely going to need him."