The punishment would be a fine for the player. We don't see those, usually they
are posted in the locker room and that's it.
When there was jai-alai in CT there was a written 'Best Efforts' rule. It's on the bottom of page 64 of this book on parimutuel regulations. Section (i):
"Jai alai being a game of skill, the winning or losing of a point depends entirely on the individual player's skill and ability, and it shall be the duty of each player at all times to make every possible effort to complete a play. If in the opinion of the court judges or the division representative, a player shows lack of interest and does not use his best efforts while competing in an official game, the offender shall be in violation of the best efforts rule."
The words are clear....DUTY....AT ALL TIMES....EVERY POSSIBLE EFFORT
The document says both the judges and the players' manager have the authority to recommend punishments for a player who commits any violationl
And notice the best efforts rule leaves it up to the OPINION of the court judges or division (meaning parimutuel division) representative.....they don't need to prove anything. If they feel you didn't try then you are guilty.
In the real world either the players' manager sees a lack of effort and issues a fine.....or the judge sees it, calls the players' manager who then issues a fine. If the division rep calls you out on it then look out for your career. And repeat violations likely means no contract next time around.
Best Efforts rule