With the NBA and NBPA agreeing to an expanded set of rules and guidelines to reduce the spread of COVID-19, the most important rule in the eyes of the league concerns guests while teams are on the road.

"I think the headline of this, and there's a lot, the most important one to the teams was to end the guests in the hotel rooms," said Adrian Wojnarowski on The Lowe Post.

"In the story I posted on ESPN.com, I quoted an executive of saying that was 'kind of the Mack truck driving through all of our protocols.'"

The NBA preferred having that rules in place from the start of the season and discussed it with the players, but it wasn't something the union would agree to at that point. 

"The rule allowed players to have guests, up to two guests, at the hotels," said Wojnarowski. "They had to technically be family in that town or longstanding friends. Certainly, I would imagine, it was a loose definition for some of those who visited."

The league wants teams to monitor the activity of players if they violate the rule.