For years, I have been pleading with somebody in charge at Forbes Field to put clay instead of sand in the batter's box. Sand causes your feet to slip. Clay gives you a chance to keep your feet solid. So all I got for years was sand and more sand. Batters would dig holes. I come to bat and scrape dirt to cover up the holes. Suddenly this year, they put clay in the batter's box. Now I have firm footing. Now I can get a toe-hold.

As quoted in Clemente Sinks Feet in Clay To Mold Stout Swat Figures by Les Biederman, in The Sporting News (July 2, 1966), p. 8 - Baseball-related