Post Malone says LeBron James' first career ejection ain't a big deal ... matter of fact, he thinks it was a HUGE energy boost for his Cavs teammates!!
White Iverson was leaving Mastro's in Beverly Hills when we asked about LBJ's emotional blowup during Tuesday night's game against the Miami Heat -- the first of his 15-year career.
Posty says these kinda things happen in sports ... and he doesn't blame King James for getting thrown out of the game.
"F**k it, if you're passionate about it, that's cool."
We also asked Kevin Durant about his on-court rival getting ejected ... but he seemed to have a different take.