Modern Day Slavery

Is there such thing as modern day slavery, where does it happen. I have read many articles and other comments that many athletes feel like they are not in control of their life and they feel like they are in modern day slavery. I can agree with this, now it is not what slavery used to be, like going out buying people having them on chains, but there are many connections in the world today. Some athletes in the articles would say that modern day slavery is a real thing, and the fans such as the viewers really don't understand what they are feeling, the athletes will speak out but it always comes off as them being ungrateful and complain. The connections are athletes are basically bought by owners and can be technically sold to another owner whenever they feel like their value is worthless for their team. Owners in the NBA trade their players all the time, and sometimes doesn't even speak to the player and the player would find out from media or other sources like ESPN. Now is that OK, the connection is like when slavery was around they would buy slaves and if they feel like they are not useful for them they would either kill them, or just give them away to another person that needs them without even telling them ahead of time. Another connection is that the players always must follow the owners rules no matter what or they will lose their jobs, and wouldn't sometimes pay their money because their contract might not be guaranteed so they put a lot of work for the team just to be dropped. Now if that doesn't connect to slavery I don't know what will because what will masters do they will use the slaves until they aren't so good anymore and they will just drop them from their plantation. Now from this I wanted to spread the experiences and the views of athletes that feel like their is modern day slavery and we need to recognized this. Why because this happens all the time, but not just in sports in everything in the world school, and jobs in the world.