Golf star Davis Love III didn't make the cut for the U.S. Open this year, but he'll still be hittin' the links ... as a caddie for his son's PGA debut!!
24-year-old Davis Love IV -- aka Dru -- picked his dad to play wing man for his first tournament as a pro ... flippin' the duo's usual roles just in time for Father's Day weekend.
The older Love has competed in 23 U.S. Opens and has served as a captain for the Ryder Cup team ... so Dru's hoping to capitalize on his experience.