Key races is a term that probably originated around American racing although it would be fair to say that we have always been informally aware that some races produce lots of good future form whilst others produce a steady stream of losers. By winners and losers here I am talking about next time out runs. Clearly if we knew that the 2.30 this afternoon was going to have 3 winners next time out from the 8 runners we would be in a position to make money provided the odds where generous enough.

The SmarterSig site has a key race page and others also try to highlight hot races from previous form but what I want to look at in this blog is how useful are they when it comes to seeking out profit. First of all I need to define what parameters I am using so that everyone understands what is being measured. This topic can have people going up blind alleys of misunderstanding from the get go if a little thought is not spent on the method. It is also an analysis that can take many different forms and this is by no means the only slant on the topic.

Firstly I am going to look at handicap races that have had one runner come out of them. Sure more runners will appear but it is at this one emerging runner point that I will mark the race down as being a certain category of race. Let me explain with an example. At the time of writing on 22/08/2018 Surrey Blaze is running at York. His last run was in a race that has produced one future runner namely Trouble and Strife who came 2nd beaten 1.25 lengths over 14f, he then came out in the same class of race and ran well to finish 2nd again beaten 2.25 lengths over 14f.

These are some explanation needed here. First of all I will define the same class as being within 0.5k of prize money either way. Anything greater than 0.5k will be classed as a class rise and below a 0.5k drop will be classed as a class drop. We can argue about these values and they can be adjusted but for now they will do fine. I also want initially to bucket races as key races where a good run has come out of a next time out class drop, next time out class rise and next time out class same so that we can compare them as markers. For example do people overbet subsequent runners just because a race has produced a good run next time out in a higher class from its first emerging runner ?. Also what if the first emerging runner runs in a lower class and runs poorly, does this mark the previous race as a donkey race ?.

Next stop was defining ‘good run’. Again there are a few ways to do this, I chose a good run to be where the distance beaten was less than the race distance multiplied by 0.2. So for 5f its less than 1 length and for 10f its less than 2 lengths.

Now the question remains is it more favourable to blindly back horses where the first emerging horse has run well in lower, higher or the same class. Also what other tweeks or parameters might be of interest. One tweeter suggested looking at percentage of horses beaten in subsequent next time out races as a way of comparing rather than ROI%. Have your say in the comments below and in the next post we will check out some numbers.