That's a bit of a hard sell as the biggest upset. Granted Louis looked dominating coming into the fight, but Schmeling had beaten some decent fighters like Young Stribling and the great Mickey Walker (admittedly out of his depth at HW) and he'd been robbed of the title against Jack Sharkey. Douglas had beaten the likes of Page, a green McCall & Berbick, but he seemed nowhere near a threat, whereas in contrast Schmeling did.
Anyway, I'd put the 2nd biggest upset of all time as being Randy Turpin's win over Sugar Ray Robinson. Turpin had beaten some decent European Middleweights, but logically his loftiest aim would have been to make it to the final bell (seeing as SRR generally went for the KO on his European 'tours'), but instead he got his hand raised. Granted Robinson had been fighting a busy schedule, but nobody expected Turpin to win.
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