The GAA have announced that they will fine any counties that break the rule that prohibits group training over the next two months.
The rule was introduced last week and several inter-county managers got around it by either training in secret or breaking their squads up into smaller groups.
That, however, will not be tolerated this year with GAA Director General Paraic Duffy reveal that financial penalties will be imposed on any county breaking the new rule.
"Our intention this time is that if counties try to go around it, we will meet that head on," Duffy said.
Managers have been severely critical of the 'closed season' rule, while Armagh-based training expert Mike McGurn says that it could lead to - and not alleviate - burnout and injuries later in the season.