The main reason for why Stu changed from gin rummy to poker was that he was a bit too skilled at it. So good in fact, that no one possibly could equal him. Even the commonly called experts who were supposed to be the greatest at gin were blow away when they competed against Stu Ungar. One such gin rummy player was Harry Stein, nicknamed, "Yonkie". Mr. Stein suffered such a humiliating beating at the hands of mr. ungar that he evidently stopped playing it as a pro and never resurfaced at a gin tournament.
Certainly, with a notoriety like that it wasn’t very long before gamblers became afraid of gambling against stu. He could not find any games and in his boredom he began doing something no one had done before. He issued starting handicaps to potential competitors in the high hopes that they may play against him if they thought they had an advantage. He deliberately began from a bad arrangement and one story has it that he even competed with a regular cheater. Mid game, he get advice that the bad egg was at it again but Stu Ungar assured that he deduced of the chicanery and he would still actually win, which he did, of course.
The same problem followed Stu Ungar to sin city. He won so often that the casinos started requesting that he not to play on their casinos anymore. The reason for it was that other casino clientele would not sit at the poker table if Stu was playing.
Stu Ungar is recollected better for his achievements in texas hold’em poker but he always maintained that he was considerably more skilled at gin rummy.
He beat Doyle Brunson in the WSOP in 1980 to become the youngest world champion. Due to his looks that made him appear far younger than he actually was, he got the nickname, "The Kid".