The honor goes to pleasant and perky, harmonica-driven "I Should Have Known Better," the second track off A Hard Day's Night. What elevates it from good to great is John's vocal on the bridge. In a Roy Orbison-like fashion, it seems to keep unfurling, never settling on a firm melody but always flowing smoothly. Moments like it were the small, unheralded building blocks of The Beatles' greatness.
"I Should Have Known Better":
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