For the second year in a row, American tennis player Jack Sock had to forfeit his U.S. Open match due to cramping.
The 28-seed collapsed due to the heat while leading 6-4, 6-4, 3-6, 1-2 against 107-seed Ruben Bemelmans, despite taking preemptive Ibuprofen between the third and fourth sets.
Temperatures at the courts in the Queens borough of New York City got over 90 degrees on Thursday, with humidity nearing 50 percent. A heat rule was in effect for the women, but there is currently not a rule in place for the men.
Sock had to be helped off the court, but did not need to go to a hospital.
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