Sorry, Wayne Gretzky ... seems the grandkid's got the golf genes and not the hockey ones -- 'CAUSE LOOK AT THE SWING ON DUSTIN JOHNSON AND PAULINA'S SON!!!
DJ and Paulina had an impromptu range sesh with their 2-year-old outside their home Tuesday ... and thank God someone brought the camera -- 'cause the Great One's grandson can seriously hack it.
Watch the clip ... River Johnson has the classic DJ backswing and he keeps his head down throughout the whole stroke. Plus, he even takes a little bit of a divot!