NEW YORK • Nick Kyrgios has said that he has no devotion to tennis and probably never would, after completing a "diabolical" Grand Slam season with a drama-charged first-round defeat at the US Open.
The Australian complained of a "dead" shoulder during his 6-3, 1-6, 6-4, 6-1 defeat by compatriot John Millman on Wednesday before revealing far deeper concerns during an extraordinary post-match media conference.
Shattered by his latest flop, he admitted his coach deserved better when asked if he would continue working with Frenchman Sebastien Grosjean beyond the Open.
"I don't know, honestly. I'm not good enough for him," Kyrgios said. "I'm not dedicated to the game at all."
After winning an unprecedented 20 from 20 matches against lower-ranked rivals at Grand Slams, Kyrgios has since suffered upset losses at five straight Slams.
His troubles have coincided with the surfacing of a hip injury at last year's US Open when he retired mid-match in the third round, before the same issue forced him to abandon his Wimbledon campaign.
Kyrgios said his latest shoulder problem, which emerged early in the third set against Millman, came out of the blue.
"I have had a diabolical year at these Slams. It doesn't surprise me," he said.
"It's just the story of my career, really. I will have good weeks; I'll have bad weeks. It's just a roller coaster."
The world No. 17 enjoyed one of his best weeks a fortnight ago when he reached his first Masters 1000 final in Cincinnati. Now he feels exasperated.
"In Cincinnati, I was not doing anything different. I was probably less dedicated than I was this week," Kyrgios said.
"I was playing basketball... I was having ice cream... I was less dedicated. And this week I was dedicated, and my shoulder starts hurting. I don't know."
Men's fourth seed Alexander Zverev was also left stunned after he was beaten by Croatia's 61st-ranked Borna Coric 3-6, 7-5, 7-6 (7-1), 7-6 (7-4).
After Britain's second-ranked Andy Murray withdrew on Saturday, the 20-year-old Zverev, the highest-ranked player in his half of the draw, appeared to have the perfect schedule for a deep run at the US Open.
He reached the New York hard courts off his best Grand Slam result, a fourth-round run at Wimbledon, and his five ATP titles this year included back-to-back US Open tune-up crowns at Washington and Montreal, beating Roger Federer in the Canadian final.
"It's upsetting," he said. "I just played a very, very bad match, so it's unfortunate."
He made 58 unforced errors with 22 aces and 43 winners.
"Physically I'm fine. I just played very, very bad in the second and third set," he added.
"I should have won the third. I definitely should have won the fourth. My level wasn't high, so that's more of the problem."
There was better news for another youngster, 18-year-old Denis Shapovalov, who became the youngest man in 10 years to reach the US Open third round on Wednesday.
The 18-year-old Canadian qualifier stunned French eighth seed Jo-Wilfried Tsonga 6-4, 6-4, 7-6 (7-3), a victory which followed a win over Rafael Nadal in Montreal last month.
He will next face Britain's Kyle Edmund today for a place in the round of 16.
THE GUARDIAN, AGENCE FRANCE-PRESSE