Paragraph 12 of the NBA Uniform Player Contract reads as follows:

12. OTHER ATHLETIC ACTIVITIES.
The Player and the Team acknowledge and agree that the Player’s participation in certain other activities may impair or destroy his ability and skill as a basketball player, and the Player’s participation in any game or exhibition of basketball other than at the request of the Team may result in injury to him. Accordingly, the Player agrees that he will not, without the written consent of the Team, engage in any activity that a reasonable person would recognize as involving or exposing the participant to a substantial risk of bodily injury including, but not limited to: (i) sky-diving, hang gliding, snow skiing, rock or mountain climbing (as distinguished from hiking), rappelling, and bungee jumping; (ii) any fighting, boxing, or wrestling; (iii) driving or riding on a motorcycle or moped; (iv) riding in or on any motorized vehicle in any kind of race or racing contest; (v) operating an aircraft of any kind; (vi) engaging in any other activity excluded or prohibited by or under any insurance policy which the Team procures against the injury, illness or disability to or of the Player, or death of the Player, for which the Player has received written notice from the Team prior to the execution of this Contract; or (vii) participating in any game or exhibition of basketball, football, baseball, hockey, lacrosse, or other team sport or competition. If the Player violates this Paragraph 12, he shall be subject to discipline imposed by the Team and/or the Commissioner of the NBA. Nothing contained herein shall be intended to require the Player to obtain the written consent of the Team in order to enable the Player to participate in, as an amateur, the sports of golf, tennis, handball, swimming, hiking, softball, volleyball, and other similar sports that a reasonable person would not recognize as involving or exposing the participant to a substantial risk of bodily injury.


He has every right to get suspended and fined.