"I'm behind Jemele -- I support her," Durant told us outside Poppy in L.A.

Donald Trump came at ESPN on Friday for Hill's "white supremacist" tweet -- demanding the network "apologize for untruth" ... this after White House press secretary Sarah Huckabee Sanders called Hill's comment a "fireable offense."

Of course, KD has his own issues with POTUS -- remember when he told us he "don't f**k with" the Donald? Yeah, not a fan ... but still, having an MVP publicly support Hill is a HUGE deal.