Drake and Michael B. Jordan showed up Thursday night to watch Bronny James -- LeBron's 16-year-old son -- take on the Etiwanda Eagles in their regional semi-final basketball game.

They might as well have been watching the Lakers in the Finals though, as they were really getting into the action from their courtside seats ... cheering on Bronny and Sierra Canyon's other star -- UCLA commit, Amari Bailey.

At one point in the first half, Drake was seen giving Bailey a pep talk, and it must have worked, because he did his best to keep the Trailblazers in it, leading the team with 37 points.

Bronny didn't score much other than a late three, but it wasn't enough in the end -- Sierra Canyon got beat 82-76 and lost out on a place in the regional final to end their season.

Of course, this wasn't the first Bronny game to draw a star-studded crowd. Just last week ... his famous father attended and brought along some past teammates -- J.R. Smith and Jared Dudley. Drake was there for that one too.

That game was Bronny's first of the season after missing most of it because of a torn meniscus he suffered in February. It was also a loss, so it's worth noting ... Sierra Canyon was 0-2 this season when Drake was in attendance. Hmm ... maybe the curse is back.