From 1972 to 1977, Johnson was the public address announcer for the tracks of the New York Racing Association.
In 1977 he moved to the new Meadowlands Racetrack in New Jersey, calling both Thoroughbred and harness racing.
Even though Johnson's Triple Crown TV spot went to Tom Durkin when televising rights shifted from ABC to NBC, he has continued to call the three spring classics for radio, on Premiere Radio Networks and Westwood One.
In 2007, Johnson missed calling the Kentucky Derby at Churchill Downs for the first time since 1977, when the rights shifted from Westwood One to ESPN Radio.
In 2005, 2007, 2008, 2009, and 2010, Johnson made voice appearances on the Late Show with David Letterman on the day prior to the Kentucky Derby, performing a sound bite of his signature phrase "...and down the stretch they come!"