Sam Amick, and Jeff Zillgitt

USA TODAY

When NBA Commissioner Adam Silver sent his digital missive on Monday, warning team owners of “significant penalties” if they didn’t follow league protocol on resting players, it was fair to wonder about the timing of the tough talk.

It’s one of many complicated questions about this increasingly relevant matter.

Why issue the memo now?

Because just one week after the Golden State Warriors rested four players for an ABC Primetime game (produced by their partner, ESPN) against the San Antonio Spurs, yet avoided Silver’s wrath because they followed league protocol, the Cleveland Cavaliers provided the tipping point in this situation by breaking policy on the same, nationally televised stage. The Cavs’ failure to list Kyrie Irving (left knee tightness) and Kevin Love (rest as part of his recovery from left knee surgery) on the injury and illness report that was due by 5 p.m. local time the day before their game against the Los Angeles Clippers, while also failing to report the plan to rest LeBron James in a timely manner, was the root of Silver’s angst, according to a person with knowledge of the situation.

The person spoke to USA TODAY Sports on the condition of anonymity because of the sensitivity of the situation.

What is the league's protocol?

According to the “Injury and Illness Reporting Procedures” in the league’s operations manual, which is available to teams but not the public, a “participation status” must be designated and specific injuries and illnesses identified by 5 p.m. local time on the day before a game. Back-to-backs are treated differently. Teams have until 1 p.m. local time on the day of the second game to designate injuries. Silver detailed the league-wide expectations regarding resting players in his memo.

“Teams are required to provide notice to the league office, their opponent, and the media immediately upon a determination that a player will not participate in a game due to rest,” he wrote. “Failure to abide by these rules will result in significant penalties.”

More on NBA stars resting:

What's NBA commissioner Adam Silver's philosophy on players resting?

Adam Silver to owners: 'Significant penalties' for breaking rest protocol

Why were the Cavs in the wrong and the Warriors were not?

While the NBA hasn't fined the Cavs and doesn't intend do, general manager David Griffin received a call from the league “seven minutes” after it was announced on the day of the game that James, Irving and Love were out. It was the first game of a back-to-back set, meaning they were required to hit the 5 p.m. day-before-game deadline. According to an injury report submitted to the NBA hours after the deadline the day before the game, only Kyle Korver and Iman Shumpert were listed as injured. If Irving and Love were questionable or not going to play against the Clippers, they should’ve been on the injury report.

“Yeah, they were not happy,” Griffin told ESPN of the call from the NBA.

The Warriors, meanwhile, had saved themselves by being more transparent.

After Golden State lost to Minnesota on March 10, Warriors coach Steve Kerr announced the plan to rest Stephen Curry, Klay Thompson, Draymond Green and Andre Iguodala the following day against the Spurs. There is also, it seems, some sympathy being afforded to the Warriors because of the absurdity of their schedule during that time.

Including the Spurs game, the Warriors had played in eight cities in 13 days. Some suggested that the Warriors players should’ve rested against the Timberwolves, thus preserving the marquee matchup against the Spurs the next day. Their chosen strategy, though, meant three days’ rest for their players instead of two.

“I’m in constant contact with people in the league; we all work together, we really do,” Kerr said on Friday regarding the decision. “Nobody (from the NBA) called me to complain, or say ‘Well, how could you do this?’ There’s nothing like that. Adam is all ears. There’s an awareness on the league’s part that we’ve got to do everything possible, not only with the length of the season – which they’re working on next year, extending it by a week, or 10 days – but sort of examining the checkerboard nature of the schedule - especially if you have key games that you’re trying to promote. Maybe take a look, maybe try to make sure both teams are rested and not at the end of some long odyssey."

More on resting players:

Cleveland Cavs hear from NBA office after sitting Big 3 in loss to Clippers

Golden State Warriors expose NBA's rest problem as stars miss key games

One simple solution to the NBA's problem with players resting

How does television revenue factor in?

In Feb. 2016, the NBA agreed to a television rights contract with ESPN and Turner worth $24 billion over nine years. The deal has since become the financial lifeblood of the league, the very reason that player salaries are soaring to unprecedented levels while the media companies footing the bill cross their fingers that the calculated risk pays off.

Naturally, TV execs aren’t thrilled with the idea that the biggest stars are routinely missing from showcase games. And as the Nielsen ratings for “Live/Same-Day viewing” below show, they have every reason to be upset.

Of note: the Cavs-Clippers game not only had the lowest viewership of the lot – and by a lot – but half the viewership of the only other Clippers game of that bunch.

Jan. 21 (Spurs-Cavs): 3.6 million

Jan. 28 (Clippers-Warriors): 3.3 million

Feb. 11 (Warriors-Thunder) 6.0 million

Feb. 25 (Bulls-Cavs) 2.4 million

March 11 (Warriors-Spurs) 2.45 million

March 18 (Cavs-Clippers) 1.65 million

And therein lies the trickiest part of Silver’s position.

He is the basketball and business boss of the league, the guy whose extensive background working with NBA Entertainment before becoming commissioner taught him plenty about the balance that must be struck here. He is also a David Stern protégé, having worked alongside the former commissioner for 22 years before assuming this seat.

He hasn’t come with the heavy hammer just yet, a la Stern in 2012 when he fined the Spurs $250,000 for sending their stars home via Southwest rather than playing them in a late-November TNT game against the Miami Heat, but he’s clearly peeved about this problem. And so, per the memo, he has implored owners to be more involved in the process.

It’s a request that could come with some consequence, the kind of slippery-slope potential for front office folks that will be discussed in detail at the April 6 Board of Governors meeting. He has also acknowledged the problems with the schedule, vowing to continue looking closely at the matter and discuss possible changes that could also aid the problem.

But the warning shot has been fired, with teams now on notice by way of Silver’s words. Next time, it’s quite clear, action will be taken.

Follow USA TODAY Sports' Sam Amick on Twitter @Sam_Amick. Follow USA TODAY Sports' Jeff Zillgitt.