On Saturday night, it seemed a foregone conclusion that we'd see Kentucky Derby and Preakness Stakes champion California Chrome run for a Triple Crown at the Belmont Stakes on June 7.
But on Sunday morning, the horse's trainer Art Sherman said that there "might be an issue" over a rule disallowing nasal strips at horse races in New York, where the Belmont is held.
Here's a quick glance at what you need to know about the controversy:
What are these nasal strips that horses wear?
Much like the nasal strips many people wear to sleep – or the ones NFL players have worn for years – they're adhesive strips that are worn across the bridge of the nose and improve air flow into a horse's nostrils.
According to Flair Strips, a company that manufacturers them, they "are self-adhesive strips that promote optimum respiratory health of equine athletes at all levels by reducing airway resistance and providing improved airflow when your horse needs oxygen most.
"During exercise when horses begin to breathe hard the soft tissues overlying the nasal passages are sucked in, reducing the airway diameter. This reduction in diameter causes greater resistance to air flow into the lungs. Flair Strips gently support the soft tissues over the nasal passages providing reduced airway resistance during exercise."
How does all this affect California Chrome?
California Chrome has worn a nasal strip throughout his six-race winning streak. And having maximum air flow could make a difference in the 1 1/2-mile Belmont Stakes, which would be the longest race the horse has ever run.
"I think it gives him that extra oomph, especially if you're going 11/2 miles," Sherman said Sunday. "Anytime you can have a good air passage, it means a lot."
Obviously the horse racing world will be watching closely, as a Triple Crown would be a historic event for the sport. There hasn't been a horse to win the Kentucky Derby, Preakness and Belmont since Affirmed in 1978.
Why wasn't this an issue at the Preakness?
Horse racing's rules are governed on a state-by-state basis, so certain regulations may differ between, say, the Preakness and the Belmont Stakes (held in Elmont, N.Y.).
California, Kentucky and Maryland have no regulations prohibiting the use of nasal strips, which have been common in the sport for about 15 years. In New York, the strips are allowed in harness racing but not for thoroughbreds, though the decision ultimately lies with stewards governing each track.
The Belmont stewards are expected to make a ruling on whether California Chrome can wear the nasal strip early this week.
Has a controversy like this ever happened before?
Actually, yes, a similar situation unfolded in 2012, when New York officials prohibited I'll Have Another from wearing a nasal strip in his attempt to complete a Triple Crown run. Trainer Doug O'Neill was going to run his horse without the strip, but it ended up being a moot point, because I'll Have Another scratched from the Belmont because of a sore tendon.
Ultimately, will California Chrome run on June 7?
Even if the Belmont officials maintain their ban on the strips, it's hard to think that the horse's owners would pass up a chance at history over something like this. So, the best guess is that this controversy will only be a footnote in three weeks.
But we can't say for sure until the stewards make up their mind and California Chrome's connections announce that the horse will compete. For now you'll just have to hold your breath (pun intended).