Talk about a terrible Sunday. 

One bold gambler put a whopping $506,000 on the Browns to cover as 3.5-point home underdogs at a William Hill book at the Ocean Casino Resort in Atlantic City. Rovell.

Half a million dollars gone as the Browns offense struggled at home.

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Per Rovell, that bet is the biggest of the NFL season so far and the single biggest a William Hill spokesman could remember.

That bet reportedly ran counter to the betting action for the game, with bettors heavily favoring the Rams.

That 20-13 final score resulted in most sportsbooks taking a bath on what was apparently the heaviest-bet game of the season so far.

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