Last year, Justified won horse racing's triple crown. (Morry Gash/AP file)

The 145th running of the Kentucky Derby will take place Saturday at the hallowed grounds of Churchill Downs in Louisville, where a field of 19 horses will race a mile and a quarter for eternal glory.

The Derby is quite obviously the biggest day on horse racing’s calendar — the sport’s Super Bowl, mixed with a heavy dose of Mardi Gras and fancy hats.

NBC will go on the air Saturday afternoon with nearly five hours of coverage, beginning at 2:30 p.m. Eastern time with the broadcast continuing until 7:25 in the evening. That creates a unique proposition, with nearly five hours of television built around a race that lasts for only two minutes. (This year’s post time is 6:50.)

Here is the back-of-the-napkin math: NBC produces 260 minutes of a pre-race show and approximately 33 minutes of post-race content, sandwiched around 120 seconds of Derby action. In other words, the ratio of pre-show, post-show and commercial content to the actual event itself is a somewhat hilarious 293 minutes to 2.

Indeed, no other sporting event delivers so much buildup for such a short burst of action. That makes the Derby a sports TV anomaly: The pregame show is, essentially, the entire event.

“You wonder how can you do five hours on one topic that’s only two minutes,” NBC host Mike Tirico said. “But the show isn’t just the race. It’s a lot of the party around it.”

NBC does not like to think about the five hours leading up to the Derby as simply pregame, but more as an immersive lifestyle show. There is a full day of programming that looks at the quirks of the Derby party, including mint juleps and A-list celebrities. The network also brings out an array of talent to fill airtime. Old standbys include hockey analyst and horse savant Eddie Olczyk, while Denver Broncos star linebacker Von Miller and NASCAR legend Dale Earnhardt Jr. are new to the broadcast. And this year, with the increased legalization of sports betting, Derby coverage will lean more heavily on handicappers.

But for an audience that is made up mostly of viewers who have minimal knowledge of the sport, the extended buildup also provides a chance to introduce a new crop of 3-year-old colts.

“We don’t have to try and tell the Tom Brady story for the 38th time,” Tirico said.

NBC does show four races ahead of the Derby — Old Forester Turf Classic, anyone? — so technically there is more racing than the two minutes of the Derby. But even these other races on the day-long broadcast feel like preamble to the main event.

Viewership increases steadily throughout the day. Last year, average viewership peaked on NBC during the 6:30 half-hour time slot, with 16.1 million viewers. The day began with 2.6 million between 2:30 and 3. And that gradual building of momentum helps to heighten the drama of the main event.

Time (ET) Average viewers for 2018 Kentucky Derby coverage on NBC
2:30 2.6 million
3:00 3.0 M
3:30 3.6 M
4:00 4.3 M
4:30 5.2 M
5:00 6.4 M
5:30 8.0 M
6:00 11.3 M
6:30 16.1 M
7:00 12.9 M

Jerry Bailey, former jockey turned NBC analyst, noted that his workday is much longer now that he’s on TV than it was when he was riding.

“I’m out there at 6:30 in the morning in this job,” he said. “At least now lunch is included.”

The brevity of the event and the quick-twitch reflexes it requires of its announcers, however, remind Bailey of his jockey days. He brings with him to the set a thick binder of notes on all of the horses, although the vast majority of his research never makes it to air.

“You do all this preparation, and you don’t use most of it because only one horse wins,” he said. “You basically have less than a minute from when the horse crosses the finish line to when you’ve got to have your analysis ready. And if it’s a long shot, I’m scrambling for my notes.”

He added, “In the Derby, everything happens pretty fast."

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