Australia's Nick Kyrgios struggled with a shoulder injury as he lost to compatriot John Millman at the US Open - admitting: "I don't know what to do."
The 22-year-old 14th seed went down 6-3 1-6 6-4 6-1 in the first round in New York.
Kyrgios looked to have taken control of the match before he hurt his shoulder in the third set.
"One serve and my arm's totally dead," he told the physio while receiving treatment.
"I don't know what to do. It's so dead and numb, it's incredibly weak. I wasn't feeling it at all, and all of a sudden, bang, with one serve.