By Byron Rogers, @Perf_Genetics
This weekend saw the running of two classics—one on each side of the Atlantic—run over roughly the same distance. The Belmont Stakes (gr. I), run in New York at Belmont Park over 12 furlongs, was won in a stirring finish by Tonalist, and the Epsom Derby (Eng-I), run at Epsom Racecource in England over an undulating 12 furlongs and 10 yards, was won in a dominant fashion by the well bred Australia.
American racegoers were given a respite from the 2:30+ times of the past four runnings of the Belmont; Tonalist completed the distance in 2:28.52, which is right on the average time of the past 50 Belmonts (2:28.65). At Epsom, Australia completed the testing circuit in 2:33.63, which was a full 2.5 seconds faster than the 50-year average for the Derby and the fifth fastest time in the past 50 years behind the insanely fast effort of Workforce in 2010.
Workforce actually ran faster (2:31.30) than the Belmont Stakes winner Drosselmeyer (2:31.60) that year, which is the only time in the last 50 years that this has occurred. In fact, the average time difference between the races puts the Derby 7.5 seconds slower than the Belmont. Plotting the raw winning times of the Belmont Stakes and Epsom Derby for the past 50 years (1965-2014) makes interesting viewing and shows that the gap in time between these races is starting to narrow.
Based on the data and the linear trend line generated, the Derby winner is getting considerably faster. Even if we drop out the inordinately slow times of Teenoso and Shergar, the trend for the Derby over the past 50 years still heads towards a one-second improvement in raw times over the period.
Visually the Belmont finishing time data looks as though it is just getting marginally slower over the same period, but the reality is that it appears that way due to two outliers in Secretariat (2:24) and High Echelon (2:34), and removing these outliers paints a different picture.
From the chart above you can see that the linear trend of the data suggests that over the past 50 years the Belmont winner is trending slower by about a second, or six lengths in handicapping terms.
Explaining the decline or improvement in raw time isn't easy to do. Like a lot of things, there is probably a lot of correlation between some theories (introduction of Lasix; increase in inbreeding; alteration of training techniques; track management; value of race; etc.) with the change in raw times. But correlation doesn't mean causation, and much to the dissatisfaction of many, given the long time it takes to measure change in the Thoroughbred, establishing the true cause(s) may not ever be achieved.