A cranky right serving shoulder hampered Nick Kyrgios in his 6-3, 1-6, 6-4, 6-1, US Open defeat to Australian compatriot John Millman today.

It was Kyrgios' second straight Grand Slam first round exit and the second major in a row where a physical issue killed his major hopes.

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“My arm felt numb,” Kyrgios said. “What else do you want me to say? My arm is not broken, but it was sore.”

In a soul-baring post-match press conference, a candid Kyrgios conceded fully committing himself to the sport is “probably not” going to happen.

“I don't know. I always get asked the question, I don't know,” Kyrgios said. “I really don't know. Probably not, honestly no.”

The pained departure from New York completes a dismal Grand Slam season in which Kyrgios managed just two match wins in four majors.

Asked if he plans to continue working with coach Sebastien Grosjean, Kyrgios replied “I’m not good enough for him” adding he believes the two-time Wimbledon semifinalist is more dedicated than Kyrgios himself.

“I don't know, honestly. I'm not good enough for him,” Kyrgios said. “You know, he's very dedicated. He's an unbelievable coach. You know, he probably deserves a player that is probably more dedicated to the game than I am. He deserves a better athlete than me.”

Though Kyrgios played inspired tennis defeating Rafael Nadal and David Ferrer in succession to reach the Cincinnati final earlier this month, he said his sometime apathetic off-court approach continues to hurt him.

“I'm not dedicated to the game at all,” Kyrgios said. “You know, (Grosjean) helped me a lot, especially with the training, in training sessions.

“There are players out there that are more dedicated, that want to get better, that strive to get better every day, the one percenters. I'm not that guy.”

Photo credit: Western & Southern Open Facebook