I'm afraid it's you against the world on that one. By far the best sport on the planet is football/soccer, followed by boxing.
Tennis is my favorite , First of all , it is not a team game in whihc you have to depend on one's tallent . But in tennis , there is no need.
Which sport could possibly be more popular than soccer? I think you're a little mistaken: "Association football, more commonly known as football or soccer, is . . . widely considered to be the most popular sport in the world." Souce: Wikipedia
Football, as in American football. Followed closely by Baseball. Then hockey and basketball at the bottom.