The main basis for why Stu Ungar changed from gin rummy to poker was that Stu was a little too good at it. So good in fact, that no player was able equal him. Even the commonly called champions who were supposed to be the most favorable at gin were devoured when they played against Stu. One of these gin masters was Harry Stein, nicknamed, "Yonkie". Harry Stein was handed such a humiliating beating at the hands of mr. ungar that he evidently quit participating in it professionally and never resurfaced at a gin rummy tournament.
Certainly, with a honor like that it was not too long before players became afraid of wagering against stu. He couldn’t find any games and in his agony he started doing something no one had performed prior. Stu offered starting handicaps to likely opponents with the high hopes that they might just compete against him if they believed they had an advantage. He deliberately started from a bad arrangement and one account has it that stu even competed against a regular absconder. Amid the match, he received warnings that the cheater was at it once more but Stu Ungar stated that he knew of the chicanery and he would still win, which of course, he did.
The same trend followed Stu Ungar to vegas. He won so often that the poker rooms began asking him not to bet on their rooms anymore. The explanation why was that other casino players refused to be seated at the poker table if he were playing.
Stu Ungar is recollected better for his accomplishments in hold’em poker but he always insisted that he was much better at gin rummy.
He beat Doyle Brunson in the World Series of Poker in 1980 and became the youngest world champion. Because of his looks that made him appear far younger than he actually was, he got the nickname, "The Kid".