Britney Spears' Son -- Flashes Of LeBron ... Lockdown Defense In Hoops Game

Britney's kid can ball!!

Check out this footage of 9-year-old Sean Preston Federline with the nasty steal in a recent youth league game.

His dad K-Fed was so proud, he posted the video to social media ... and wrote, "ballin... Great D but gotta work on them layups."