I have my own formulation for whether I think a sport is a good sport. My knocks on baseball are that (a) it is too slow, (b) it is too contrived*, and (c) it is too static (i.e. a baseball player may be required to move swiftly a handful of times during a game. The rest of the time, he is standing around). *Basically, if an alien landed on the planet and you had to explain the sport to him, how long would that explanation take. Of every sport I can think of, it would take the alien longest to understand baseball. The alien would understand boxing and MMA in about 30 seconds, and both tennis and basketball could be explained in a matter of minutes. I think all three of those sports are awesome.
If it weren't for the numbers and terminology used in the scoring system, then yes. The winner of a "game" in tennis is simply the first to win 4 points, except that you have to win by two. And that's how I would explain it to the alien.