Someone (not Leyton Hewitt) has trademarked the phrase "Come on." http://au.sports.yahoo.com/tennis/news/article/-/7578563/come-on-lleyton-we-won-in-court/ Pretty ridiculous that someone can "own" a common phrase, but it happpens all the time. Michael Buffer owns "Let's get ready to rumble. Pat Riley owns "Three-peat." Darrell Waltrip owns "Boogity boogity boogity." Paris Hilton own's "That's hot." So, the next time you hit a winner, if you calll out, "Come on," remember you're infringing on someone's trademark.