Equinometrics

Revolutionizing how jockeys are rated.

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What is Speed Above Replacement Jockey (SARJ)?

Everybody wants to know who the best jockeys are.

  • Trainers and owners want to hire the best jockeys available.
  • Fans want to know if a change in jockey will improve their horse's chances.

But traditional jockey ratings are flawed.

  • We rank jockeys on how often they win—but winning depends on what horses they get.
  • We rank jockeys on how much money they earn—but earning money depends on the purses they get to race for.

Suppose a talented jockey gets stuck racing claimers at an out-of-the-way track. How would we ever notice them?

Speed Above Replacement Jockey (SARJ) solves this problem by measuring how many Trackmaster speed point a jockey adds to their mounts, compared to an average jockey. An average jockey has a SARJ or 0. A jockey with a SARJ of +4 adds 4 speed points on average to their mounts—which is enought to make the difference between first and second place in most races.

First in a 2022 Bloodhorse article, SARJ works off what happens when a horse changes jockeys.

  • Suppose you and I both get a chance to ride a top thoroughbred, say Quicksilver. I ride him to a speed rating of 90—pretty good. But you ride him to a speed rating of 94. That's evidence that you're a better jockey than me, by about 4 points.
  • Now suppose I also ride a claimer named Suchadrag. I ride him to a speed rating of 78&mdash. But his last jockey, Bill, only rode him to a 73. That's evidence that I'm a better jockey than Bill.
  • It's also evidence that you're a better jockey than Bill—even if you and Bill have never ridden the same horse.
Jockeys
👕 You 👕 Me 👕 Bill
Horses 🐎 Quicksilver Speed 94 Speed 90
🐎 Suchadrag Speed 78 Speed 74

SARJ averages these comparisons across about 1200 active jockeys riding 50,000 horses in 300,000 starts every year. It adjusts for changes in track, condition, age, medication, weight carried, competition, and other factors that might affect a horse's performance. The result is a single number that tells us which jockeys are really making a difference.

Want to see how a specific jockey stacks up? Let's look at an example.

How SARJ Visualizes Jockey Performance

Let's take a look at Irad Ortiz, who's been the busiest jockey in North America for the last few years. Our SARJ graph confirms that Irad was a top jockey in 2024. With a a SARJ rating of +4.5, Irad would usually win on a horse that an average jockey would race to second.

Sample

That's not a big surprise, but of course you can't hire a big name like Irad Ortiz for every race. Are there other jockeys who are just as good but not as well known?

There must be. Irad's SARJ ranked him 38th out of 1129 active jockeys, implying there were 37 jockeys whose SARJ was at least a little better, and another 30 or so whose SARJ wasn't much worse.

We can see comparable jockeys by hovering over the graph.

Boyce has won over 1,000 races and been called the "Queen of Maryland" for her success on the state's tracks. But she's never started the Preakness Stakes in Baltimore, even though her SARJ suggests she could do as well as Irad Ortiz. Villa Gomez, with over 2,000 career wins, started only a third as many races in 2024 as he did in 2011, even though his SARJ suggests he hasn't lost a step.

Curious about another jockey? Want to compare two jockeys? Look 'em up.

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