The primary reason for why Stu Ungar changed from gin to poker was that he was a tiny bit too skilled at it. So good was he, that no player was able equal him. Even the apparently champions who were meant to be the greatest at gin were crushed when they faced Stu. One such gin professionals was Harry Stein, nicknamed, "Yonkie". Mr. Stein was handed such a crushing beating at the hands of stu that he evidently quit participating in it professionally and never resurfaced at a gin tournament.
Accordingly, with a distinction like that it was not very long before people became shy of playing against mr. ungar. He could not find any matches and in his desperation he began doing something no one had performed prior. Stu began offering beginning handicaps to likely opponents in the wish that they might play against him if they believed they had an advantage. He deliberately played from a negative arrangement and one story has it that he even played against a consistent cheater. Mid contest, he get warnings that the cheater was at it once more but mr. ungar guaranteed that he knew of the dishonestly and he would still acquire a win, which he did, of course.
The same trend followed Stu Ungar into Las Vegas. He won so frequently that the casinos started requesting that he not to gamble in their rooms anymore. The reasoning behind it was that other poker room clientele would not be seated at the poker table if Stu was seated.
Stu Ungar is recalled better for his abilities in texas holdem poker but he always said that he was far more skilled at gin rummy.
He defeated Doyle Brunson in the World Series of Poker in 1980 to become the youngest world champion. Because of his features that made him appear far younger than he was, he got the nickname, "The Kid".