From Sports Illustrated:
Nack was a towering figure in the history of sports journalism, a literary wordsmith and tireless reporter whose distinctive and soaring prose is revered by his peers and generations of younger writers. He stands among the best sportswriters in the history of the genre, and in many ways, among the best writers of any kind. When he stopped typing, he was a giant personality, full of endless good charm, disarmingly well-read and all times, given to entertain...
And here's Nack's reminiscences of his favorite horse, Secretariat: Pure Heart