A veteran of Great Britain's horse racing scene has been selected to be the new track announcer at Churchill Downs.Forty-two year old Mark Johnson was among five finalists for the job. All of them were given a week's audition during the Churchill Downs fall meet.Johnson's biggest test will come on the first Saturday in May, when he'll call his first Kentucky Derby. He's never attended the event, but says he has long appreciated the spectacle from afar, particularly the playing of "My Old Kentucky Home,""I can tell you, I will have the hugest lump in my throat, it gets you, (even) four thousand miles away across the pond, so believe me when I'm....at the top of that booth, it will definitely get to me," Johnson said.Johnson, who will continue to work in Britain as well, becomes Churchill Downs' sixth announcer. His predecessor, Luke Kruytbosch, suffered a fatal heart attack last July.(Photo courtesy of Churchill Downs)