Nick Kyrgios’ unsettled Wimbledon preparation has taken another turn, with the Australian star splitting with coach Todd Larkham less than a week before the grand slam starts.

Kyrgios, who withdrew from this week’s lead-up grasscourt event in Nottingham citing illness, announced on Tuesday that he and his long-term mentor had “mutually agreed” to part ways.

“It’s never an easy decision to end a coaching relationship and to do so prior to the start of a grand slam is even more difficult,” Kyrgios said on his website.

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“But I feel that this is the right decision for me at this time.”

He said he would take guidance from his team and Tennis Australia throughout Wimbledon, before turning his attentions to finding Larkham’s successor after the tournament.

Larkham has had a long professional relationship with Kyrgios that started when he was a 10-year-old and lasted for seven years until Simon Rea took over.

They reunited after the current world No.29 split with Rea last year following his stunning upset of top-ranked Rafael Nadal to reach the Wimbledon quarter-finals.

“I’ve worked with Todd on and off for many years and he has helped me immensely,” Kyrgios said.

“I am very grateful for everything Todd has taught me and helped me with, especially during the last year.

“While our working relationship has ended, Todd and I will remain friends as he has been a very important person in my life.

“I would like to take this opportunity to thank Todd for everything he has done for me, both personally and professionally, and wish him the best.”

Kyrgios’ Wimbledon build-up has been scratchy, involving just one competitive grasscourt outing.

The 20-year-old from Canberra withdrew from this week’s Nottingham Open after being a no show in Stuttgart earlier in June because of an elbow injury.

Those tournaments were sandwiched by a first-round loss to newly-crowned French Open champion Stan Wawrinka at Queen’s last week, in a flat performance which he attributed to fatigue and having felt unwell since the French Open.

After the loss to Wawrinka, Kyrgios said he needed to “chill out” and forget about tennis for a few days.

In pulling the pin on Nottingham, he tweeted he was still sick and had been unable to practise since his 47-minute loss to Wawrinka.

But there’s hope yet for the precocious talent, who has resumed practising at the All England Club.

He also reached the Australian Open quarter-finals in January despite playing just one ATP tournament in four months leading into his home slam.

“I still feel confident,” Kyrgios said at Queen’s.

“I know that I could do some good things there and I know that I don’t necessarily need too many matches before grand slams.”

Australia’s top-ranked men’s player Bernard Tomic is also preparing for Wimbledon without Tony Roche, who began working in tandem with Tomic’s father John earlier this year.

Roche, the former long-time Australian Davis Cup coach and mentor of Roger Federer, Pat Rafter and Ivan Lendl, had planned to be at Wimbledon with Tomic.

But he remains at home in Sydney instead, unable to travel.

“That was the original plan, that he was certainly going to be helping Bernie leading into Wimbledon and at Wimbledon,” said Australian tennis great John Newcombe.

“Bernie likes Tony and they get on well, so that would have been nice.

“But Bernie should be right. He knows his way around pretty well now.”