A hundredth of a second can determine who wins. This event requires control, attention to detail, and close cooperation between horse and rider. Competing against the clock, contestants circle three barrels in a cloverleaf pattern and race back across the scoreline. Time is measured with an electronic eye timer, to the hundredths of a second. A rider may touch a barrel, but if she knocks one over a five-second penalty is added to her total time.