New Delhi, July 30 -- The week the New York Knicks ended a 52-year title drought, the city's sportsbooks were losing money faster than at any point in the mobile era.

a $2.26 billion handle, the most ever wagered in a single June in New York, and $117 million in gross revenue, down 43.3 percent from a year earlier. The New York State Gaming Commission's monthly report crystallized a paradox that neither operators nor their shareholders had anticipated: the same two sporting events that drove an unprecedented surge in wagering also stripped the books of their margin.

The Knicks clinched their first NBA championship since 1973 on June 13, eliminating the Oklahoma City Thunder in Game 7. During the championship week alone, New York's eight...