Ryan Garcia will live up to his King Ry moniker Saturday night in NYC ... 'cause the star boxer commissioned an insane iced-out crown -- with over 15,000 diamonds -- that he plans to wear as he walks to the ring! TMZ Sports has learned celeb jeweler The Ice Champ is the man behind the royal piece ... making the crown for Garcia's highly anticipated boxing match with rival Devin Haney on Saturday night at Barclay's in Brooklyn. "He was like 'let's create something where the champ of the boxing world and the champ of the jewelry world connect and make something unique,'" Ice Champ said. "We created a unique crown." (full story)