Austin Walton has been suspended 27 games by the NHL for a domestic assault incident.
Walton pleaded no contest in July to a domestic assault charge.
The NHL Players' Association is filing an appeal on Watson's behalf.
The NHL does not have a specific domestic violence policy.
"I have determined that Nashville Player Austin Watson engaged in a physical confrontation with his domestic partner," Gary Bettman said in a statement. "Today's ruling, while tailored to the specific facts of this case and the individuals involved, is necessary and consistent with the NHL's strongly held view that it cannot and will not tolerate this and similar types of conduct."