The primary reason for why Mr. Ungar switched from gin rummy to poker was that Stu was a bit too skilled at it. So skilled in fact, that no one could equal him. Even the apparently champions who were supposed to be the greatest at gin were crushed when they faced Stu Ungar. One of these gin professionals was Harry Stein, nicknamed, "Yonkie". Mr. Stein suffered such a crushing beating at the hands of mr. ungar that he allegedly quit playing it as a pro and never showed up at a gin rummy tournament.
Accordingly, with a image like that it was not very long before gamblers became afraid of betting against Stu Ungar. He could find no games and in his boredom he began doing something no one had attempted prior. Stu issued beginning handicaps to likely adversaries in the high hopes that they may compete against him if they thought they held an advantage. He deliberately played from a bad position and one story has it that he even competed with a regular bad egg. Amid the match, he get warnings that the bad egg was at it one more time but stu assured that he was aware of the chicanery and he would still acquire a win, which he did, of course.
The same trend followed Stu Ungar to vegas. He won so much that the casinos began asking him not to gamble in their rooms anymore. The basis for it was that other poker room clients would not sit at the table if Stu was playing.
Stu Ungar is remembered more for his accomplishments in texas holdem poker but he always maintained that he was far better at gin rummy.
He defeated Doyle Brunson in the WSOP in Nineteen Eighty to become the youngest world camp. Due to his looks that made him seem far younger than he actually was, he got the nickname, "The Kid".