Kyrgios was devastated after his arm went “numb” suddenly in the third set of his 6-3 1-6 6-4 6-1 first-round loss to countryman John Millman.

“I wasn’t feeling it at all and then on one serve I lost power in my arm. Just on my serve,” Kyrgios said.

“One serve, then completely dead. It’s so dead and numb. It’s incredibly weak.

“It’s just so annoying.”

Australia’s singles spearhead and also a potential doubles option, Kyrgios hasn’t dropped a set in three Davis Cup rubbers in 2017 and is desperate to be fit for the semi-final in Brussels from September 15-17.

“I’ve got time up my sleeve now. Obviously Davis Cup is one of my priorities this year. I put it right at the top of my list,” he said.

“I have put a lot of effort into Davis Cup this year. I obviously made myself available for every tie, really bought in, really gave everything.

“We are doing so well so it is my goal to win the Davis Cup, so we’ll see.”

Kyrgios’s commitment to the Cup cause is at odds with his claim after losing to Millman that he has “no dedication to the game at all”.

But he is hoping his attitude changes once he gets over his latest grand slam disappointment, the two-time major quarter-finalist only winning two matches in 2017 on the sport’s biggest stages.

“The last three months has been a nightmare, really,” Kyrgios said.

“I had such a good Indian Wells, Miami, and then Davis Cup – we had a good (quarter-final) win over America, and then things just went downhill from there really.

“Obviously I’m disappointed I lost today (but) it’s not the end of the world.

“I will get over it in probably half an hour. I will get food and watch the matches. It is what it is.”

Kyrgios also had no plans to withdraw from the US Open doubles with fellow Australian Matt Reid.

“The only reason I play doubles is because of my partner,” he said.

“Obviously Matty Reid, he’s been helping me for this whole year and I know it’s big for him to play the US Open ‘dubs’.

“I don’t know, I’m the type of guy that would probably help someone out.”

Meanwhile, Ashleigh Barty has continued her breakthrough season with another milestone win to power into the US Open’s third round.

Australia’s resurgent former junior prodigy saw off Belarusian Aliaksandra Sasnovich 6-1 7-6 (9-7) this morning to progress to the final 32 at Flushing Meadows for the first time.

Barty will next play either Slovakian world No.10 Dominika Cibulkova or American Sloane Stephens and is already guaranteed a career-high ranking well inside the world’s top 40.

-AAP