A golf fan was booted from the Scottish Open on Friday ... after he stole Rory McIlroy's club straight out of the star's bag and began playing with it on a tee box.
The bizarre scene was captured on video ... and you can see in the footage, as Rory was gearing up to hit a tee shot on hole #10 at The Renaissance Club in North Berwick -- a fan casually walked up to the 32-year-old's bag and rummaged through it.
The guy initially tried to pull out Rory's driver ... but when it got stuck, he went back into the bag and snagged one of McIlroy's irons.