It seems fortuitous that Frankie is an admirer of William Butler Yeats, who in his later years developed a style of unadorned, disillusioned eloquence and produced some of his greatest poems: lyrics that are simple, forceful and not afraid of risking cliche.
Late in the film, in his darkest hour, Frankie reads from The Lake Isle of Innisfree, the younger Yeats's pastoral dream of flight and transformation, a choice that makes sense in context.
Eastwood himself, though, is closer to the sensibility of a late poem like The Circus Animals' Desertion, whose famous image of "the foul rag-and-bone shop of the heart" might describe Frankie's gym.
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