What's the main difference between the "player" and the "athlete" in sports?

Native speaker’s answer
Rebecca
"Player" can be used to refer to any contestant in a competition or game, whether they are an athlete or not. For example, you can be a player in a card game. "Athlete" however, refers to any individual that competes in sports or athletic activities. Thus, in the sports context, both "player" and "athlete" can be used, but in the non-sport context, "athlete" cannot be used. Ex: I used to be a judo athlete. Ex: We need one more player for this poker game, do you want to join?