When does an excuse become a reason?

For fans, NBA schedule difficulties can sometimes sound like an excuse. NBA players are paid millions of dollars, the thinking goes, so why can’t they be ready to play and win two nights in a row? Even if they travel in between, they should be fine on their fancy private jets, right?

Cheri Mah, a physician scientist at the UC San Francisco Human Performance Center and someone who regularly consults with NBA teams on sleep-related issues, disagrees. In conjunction with ESPN, she’s created a formula, the Mah score, which takes into account game time, schedule congestion, travel required, recovery time, and game location for each NBA contest and then gives each game a 1-10 score. ESPN issues a “Schedule Alert” when the game has a Mah score of 8 or above.

It turns out that the Mah score of a game is insanely predictive of whether or not a team will win or lose. Since ESPN started the project, teams with a “Schedule Alert” have lost 74 percent of their games. Last year, it was 42 of 54 such contests, or 78 percent.

For a metric that doesn’t take into account team success whatsoever, this is an exceptionally significant result: The Warriors could be facing the Suns, but if the world champs didn’t get enough sleep the night before, they’d still get a “Schedule Alert." And if history is any indication, they’d be at significant risk of losing that game.

The Jazz are only part of two games with a Mah score of eight or above before the All-Star break, and both in the first week of November. Saturday night’s 103-88 loss to the Nuggets had a Mah score of 8.5. That was thanks to a contest against the Memphis Grizzlies the night before, the game being their third in four nights coming on the heels of a four-game road trip, and a late-night flight to Denver that didn’t see the Jazz get into their hotel rooms until 2 a.m.

“[It does impact us] a little bit with scheduling, because we got in so late the night before,” Jazz rookie guard Grayson Allen explained. “[We flew out] right after the game, so it kind of affects what we do the morning of the game. It was kind of different with our final walkthrough being at a later time, and not doing as much.”

And what do you know: They predictably started the game well, and faded in the fourth quarter as tired legs meant their open shots fell short. Even on layups, the Jazz didn’t always look like they had the extra inch of vertical that turn contested layups into easy ones. It was exactly what you’d expect to see in a Schedule Alert game.

On Monday, the tables will turn: Their matchup against the Toronto Raptors is a Schedule Alert for the Raptors, not for the Jazz. While it has a slightly lower Mah score — 8, not 8.5 — the factors still add up: The game will be the Raptors' third in four nights; they play the Lakers Sunday night in an 8:30 p.m. MST game, and then will have a late night traveling to Utah, even losing an hour due to the time zone change. To manage his workload, Kawhi Leonard will sit either against L.A. or Utah, though it hasn’t yet been determined which one.

That’s not to say that the Raptors won’t be a tough challenge for the Jazz, who are winless in their last three. But if the Jazz come through with a win on Monday, Raptors fatigue will be a legitimate reason — not an excuse — for the visitors.