Super Bowl Sunday is the biggest night in American sports. A popular destination to watch – and bet – on the Super Bowl is Las Vegas, Nevada.

And it was in Las Vegas, ahead of the 1986 Super Bowl between the Chicago Bears and the New England Patriots, that one enterprising casino would kickstart a new direction in American sports gambling: prop betting. It offered odds not just on the result of the game, but on the outcome of an individual event within it – whether one defensive player called William Perry, nicknamed The Refrigerator, would score a touchdown.

Today, as American sports face multiple gambling scandals, we speak to John Affleck, Knight Chair in sports journalism and society at Penn State, about that 1986 Super Bowl, the history of prop betting, and why he believes its explosion is threatening the integrity of professional sports in the US.

This episode was written and produced by Katie Flood with editing help from Mend Mariwany. The executive producer is Gemma Ware. Mixing by Michelle Macklem and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.

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