Some athletes become popular because they had such success in their athletic career. Others gain their popularity due to media attention sometimes for events unrelated to their sport or their success in the sport. Derek Jeter is probably one of those athletes where he gained some popularity through his sport, but he became so revered by the people he dated. Jeter started dating famous people and his social life gained media attention and then he became so revered as a result of this.
Once this started, then his popularity grew and grew over time. His appearance probably helps too. His good looks the way he carries himself also made him popular with people, especially women. Also, once someone gets a little popular in New York, it can grow tremendously.