Bob Baffert says he will NOT let Medina Spirit's positive drug test get in the way of his Triple Crown bid ... claiming he plans to run the horse in the Preakness this weekend.
Of course, Baffert was suspended indefinitely by Churchill Downs on Sunday after Medina Spirit popped for a banned substance following his victory at the Kentucky Derby.
68-year-old Baffert -- by far the most famous and successful trainer in horseracing history -- has repeatedly denied any wrongdoing ... but it's the 5th time one of Bob's horses has tested positive for an illegal substance in the past 13 months and many are skeptical.