Visco Grgich, was a professional American football lineman who played in the All-America Football Conference and the National Football League, at the end of his pep talk, Grgich would say "This is the way you've gotta do it!", and would promptly deliver a forearm shiver to the nearest door, wall or even one of the wooden support posts in which outdoor athletics stadium in San Francisco, California, located adjacent to Kezar Pavilion in the southeastern corner of Golden Gate Park?