According to the dictionary bias means a propensity or prepossession; bent; prejudice. Understanding what actually happens on the racetrack involves knowing how the track is playing, where the winners are coming from and why.
A track bias occurs when a certain part of the racetrack or certain running styles are favored over others, which results in a change of what would normally happen.
What a bias does is it gives a certain horse an advantage or more importantly a favored horse a disadvantage because something about the track has been added or changed.
A track bias can be caused by a variety of things. One is the weather. At Del Mar for instance, with its close proximity to the ocean, the track can change almost daily, if not hourly. Whether it’s the moisture, the salt water, the humidity, the overcast mornings, the fact remains that one has to really pay attention to where the winners are coming from at this resort course.
I remember a season at Del Mar in the 80s when every horse that got a lead and got to the rail seemed to be unbeatable. One of the press box scribes termed the inside the “jet stream” and those that recognized this bias early enough took advantage of it at the windows.
Another thing that can cause a bias is rain or a track maintenance crew that graded the dirt unequally on a certain portion of the track. Surely, there are other ways that things can change a track and cause a bias.
To be able to take advantage and recognize a bias a player must be aware of the styles of the horses running in a particular race. Know how the race should unfold and be aware of what posts the speed horses break from. By watching the races intently, a fan can get an idea of which parts of the track are kind to winners.
Sometimes horses that run on or very close to the rail seem to have that extra oomph to carry their speed the needed distance to win. Hence, the “jet stream”. But other times horses that make the lead from the inside appear to be running in quick sand the last couple of furlongs and horses that rally wide take advantage.
The great thing about a track bias and being able to decipher it early is that it can be utilized for weeks. If a speed horse that was trapped on the disadvantaged rail and stops to a halt comes back 2 weeks later and meets a similar field but draws an outside post where he can really take advantage of his speed he becomes a prime play.
Conversely if a horse was the recipient of a “bias” win, a win in which the bias helped him win, he becomes suspect the next time he races especially if he draws a bad post. For instance, if an inferior horse had won because he drew an outside post on a track that favored that position, then came back for his next race and draws the rail when the track is playing the same way, he becomes and excellent horse to bet against. And often times, because of his recent win, the public will make him the favorite leaving a juicy price on an intrinsically better horse.
The track bias issue can be tricky. One has to be able to see a real bias and to take advantage of the bias at the betting windows, one must be able to recognize the bias early enough before the majority catch on and incorporate their bets into the bias. Bottom line: watch the races, be aware of how they figure to set up, and use logic and common sense in evaluating results.