America is a very big country with a large, diverse population. That means we have all kinds of sports. As you probably know, there are many expressions used in sports. Sometimes, these expressions start to be used in everyday life.
For example, “down for the count” comes from the sport of boxing. When a boxer is knocked down, he has ten seconds to stand up again. When he is down, he is “down for the count.”
Today, we may say someone or a company is “down for the count” because of a setback or a small failure. But that doesn’t mean they are “out” yet. A fighter who is knocked down may still stand up and win the fight. Likewise, a businessman or company can lose some money or some deals but over a long time still be very successful.
Are you interested in a full list of sports idioms you can use outside of sports?
Wikipedia has a full entry: http://en.wikipedia.org/wiki/List_of_sports_idioms
Or just search around online!