You may not know him by sight, but you know of him if you have ever watched a movie that starts with a lion roaring under the words, "Metro-Goldwyn-Mayer," before the opening credits.

The "Mayer" was Louis B. Mayer, the longtime head of MGM Studios in Hollywood's classic age. For the better part of thirty years, Mayer ran the show out West, and MGM produced a plethora of pictures - and profits - under his watch.

But Mayer also played a pivotal role in California Thoroughbred racing.