LeBron James is 100% right to call out David Fizdale getting axed by the Grizzlies -- so says Jermaine Dupri, who tells TMZ Sports someone's gotta explain the shocking decision.
FYI, LeBron went to bat for his former Heat assistant coach on Monday ... after Fizdale got the boot less than a quarter of the way into the season.
"I need some answers. Feels like my man was a fall guy," James said.
Dupri echoed LeBron when we got him outside Poppy in L.A.
"We need a little understanding! What's the reason?"
Most are chalking it up to a beef between Fizdale and Marc Gasol ... so you can see why it ain't sitting well with 'Bron and J.D.