04/29/2015 4:42PM

Analyzing the Kentucky Derby's history


It’s a bit of an understatement to say that the Kentucky Derby is unlike any other race in North America. Even the most casual of fans have their Derby horse, and it’s the one day of the year that can get even non-racing fans to watch horse racing.

From a racing standpoint, the modern Derby era began in 1915, when Regret became the first filly to win the Derby, besting a field of 16. Prior to that, the race had only seen three fields with more than 10 starters, and only the inaugural Derby in 1875 had as many as 15. Following Regret’s win, the race regularly saw 15 starters, but until 1980, it was just as likely that the field would be fewer than that.

Since 1981, only three Kentucky Derbies have not used the auxiliary gate, which is needed whenever the race has more than 14 runners, and it’s been used every year since 1998.

In recent years, the Derby has also become a betting race like none other; 1985 was the first year that Churchill Downs offered exacta wagering, with the trifecta added in 1994 and the superfecta in 1996. However, the true modern era of Kentucky Derby wagering started in 2001 with the elimination of coupled entries due to a common owner or trainer and the elimination of the mutual field (which coupled the longest shots in the field as one wagering interest). Since then, no race has had fewer than 16 betting interests, and the last 10 have had at least 19.

Post position

Every year, the draw for the Derby is shown live on TV, and much is made about which post positions connections want or don’t want. The rail post is considered the kiss of death, and most owners/trainers/bettors frown on getting stuck in the auxiliary starting gate that houses horses in posts 15 and higher. But are those posts truly disadvantageous? Let’s take a look at the last 50 Derbies to see how runners from these posts have fared.

The auxiliary gate: Since 1965, there have been 38 Kentucky Derbies that used the auxiliary gate; 11 of those races were won by horses who started from posts 15 or higher. Those 38 races featured 691 total starters, for an average of just over 18 starters per race. In those races, 532 horses broke from posts 1-14, representing 77 percent of the field, and 159 started from farther out. Considering that posts 15-23 account for 29 percent of the wins in races with at least 15 starters but represent only 23 percent of the starters in those races, it’s hard to make a very strong case for downgrading horses stuck in the outside posts. Here are stats for the outside posts over past 50 Derbies:

Post Starts Win 2nd 3rd ROI
15 38 4 2 1 $1.11
16 32 4 2 2 $5.70
17 28 0 1 0 $0.00
18 24 1 4 0 $1.85
19 21 1 1 0 $1.55
20 12 1 0 1 $0.57
21 2 0 0 0 $0.00
22 1 0 0 0 $0.00
23 1 0 0 0 $0.00
Total 159 11 10 4 $1.94

The rail post: Post No. 1, on the other hand, has proven to be a statistical disadvantage over the past 50 years, especially in races with enough runners to require the use of the auxiliary gate. Since 1965, horses breaking from the rail have won only once (Ferdinand in 1986 vs. 15 others, paying $37.40 to win), and that win is the only time a horse facing at least 14 other horses has finished in the exacta. Since 1965, when an auxiliary starting gate is used in the Derby, horses breaking from the rail are a combined 38-1-0-3 for a 98-cent return on investment, and prominent contenders in that time to fail from the rail post include Lookin At Lucky as the favorite in 2010, Fly So Free as the 3-1 second choice in 1991, and Risen Star at 5-1 in 1988.

Other random stats

Eleven of the past 24 Kentucky Derbies were won by horses coming off a win in their previous start, including the winners of the past four Derbies. Nine of those 24 were won by ones who ran second last out. No horse coming off a third-place finish has won the Derby in that time (70-0-6-2), but four of those races were won by horses who raced fourth in their final Derby prep (38-4-3-3, $7.49 ROI).

Funny Cide in 2003 was last horse to win the Derby coming out of the Wood Memorial. Runners going from the Wood to the Derby are 23-0-0-0 since.

Grindstone in 1996 was the last Kentucky Derby winner not to use Lasix. Only eight since have run without it. Mubtaahij will be the first Derby runner since 2005 not to receive Lasix.

Todd Pletcher has a 40-1-2-3 record in the Kentucky Derby, for a 23-cent ROI, winning in 2010 with Super Saver as the 8-1 second choice. He ran second in 2006 with Bluegrass Cat at 30-1 and Invisible Ink in 2001 at 55-1.

In the past 50 years, the post-time favorite has won 15 times, the second choice has won 11 times, and the third choice won three times. No fourth choice in the wagering has won the Derby in the past 50 years.

Spectacular Bid in 1979 was the last favorite to win at odds lower than 2-1. Since then, five have failed: Chief’s Crown was third in 1985 at 6-5, the Easy Goer/Awe Inspiring entry ran second and third in 1989 at 4-5, Mister Frisky ran eighth in 1990 at 9-5, Arazi ran eighth in 1992 at 4-5, and Point Given ran fifth in 2001 at 9-5.