A Light Heavyweight Grand Prix was originally expected to start at Dream 14, with an eight-man tournament. However, Dream 15 hosted the opening round of the Grand Prix, with only a four-man tournament.[2]
After Jake O'Brien failed to make weight, his Light Heavyweight Grand Prix Opening Round bout against Gegard Mousasi was made into a 212-lbs catchweight bout. O'Brien started with a yellow card, a point deduction and a 10% purse deduction.