Years ago, the legendary Bob Martin opened what came to be known as the Las Vegas Line during his stints at Churchill Downs and the Plaza.

There was a time many years ago when most of the betting lines did in fact originate from Las Vegas. But what does that really mean when we hear these expressions? Is there one sportsbook in Las Vegas setting all the lines? Do all the sportsbooks get together and agree on what the line should be? Does Las Vegas even really set the line at all? You will often hear media outlets say “Vegas” opened the line this or “Vegas” has the line at that.

By Matt Metcalf / opening line can be a term that is thrown around pretty loosely when it comes to sports betting.