EXCLUSIVE

Tiger Woods just lost one of his precious golf titles ... to a golfer with cocaine issues.

Our links spies tell TMZ ... Dustin Johnson shot a 61 last Tuesday at the Sherwood Country Club in Thousand Oaks. That beats Tiger's record score at Sherwood by 1 stroke.

Tiger held the Sherwood record since 2007 and hit that mark again last year.

Here's the coolest part. Dustin -- who's engaged to Wayne Gretzky's daughter Paulina -- broke the record while shooting the round with Wayne and his wife. Under USGA rules, the score must be signed by a witness, and Wayne did the honors.

Dustin took a leave of absence from the PGA in July after he tested positive for cocaine.