Complex sentence: John Clarke was the first actor to play Mickey Horton on the American soap opera "Days of Our Lives", starring on the show from its debut in 1965 until he was forced to retire early in 2004 due to health concerns.
Split into simpler sentences: John Clarke was the first actor to play Mickey Horton on the American soap opera Days of Our Lives. He was forced to retire early in 2004 due to health concerns.