Nascar threw a bash at Kansas Speedway in October to thank Sprint Corp. for being stock-car racing’s top sponsor for 13 years. More than 800 Sprint employees received hot dogs, burgers and seats to a nail-biting race.

One thing was missing: a new sponsor. Despite knowing for two years that Sprint was leaving, Nascar didn’t announce a replacement until December, when it said energy-drink maker Monster Beverage Corp. had won naming rights to the top-tier racing circuit.

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