5. Can't afford to trade: Luka Doncic
This may be the most obvious player on this list, but the Dallas Mavericks can't afford to trade Luka Doncic by any means. Doncic has been with Dallas since they drafted him in 2018, and he is playing the best basketball of his career this season.
Doncic is averaging 31.8 points, 8.5 rebounds, 8.6 assists, and 1.3 steals per game while shooting 49.4 percent from the field and 39.5 percent from downtown. Luka is also coming off one of the best games of his career, as he became the first player in NBA history to drop a 25-point triple-double in the first half of a game.
Doncic's conditioning from the summer has allowed him to become even better, and he is someone that Dallas can't afford to trade due to the fact that he is just now entering his prime. We likely haven't even seen the best version of Luka yet, and landing such a great talent through the draft is almost impossible.
The Mavs need to continue to build around him and Kyrie Irving with the hope that they can make an NBA Finals push soon. Luka could go down as one of the greatest NBA players of all time, and Dallas would become the laughingstock of the league if they decided to move him elsewhere.
Luka should be untouchable.