Andy Murray
File photo of Murray training ahead of Brisbane InternationalPATRICK HAMILTON/AFP/Getty Images

Former world number one Andy Murray has withdrawn from the ongoing ATP 250 tournament -- Brisbane International -- due to pain in his right hip, raising concerns over his participation in Australian Open, starting January 15.

Murray said on Tuesday (January 2) that he is still not fit enough to compete at the highest level. Notably, the Brit has not played competitive tennis since losing Wimbledon 2017 quarter-final to Sam Querrey.

"I am very disappointed to be withdrawing from the Brisbane International," Murray said, as quoted by ATP's official website.

He added: "I came here [Brisbane] with every intention of making a strong start to the year, but sadly my team and I don't feel that I'm where I need to be just yet to compete at the highest level."

Update: Check out this Instagram post from Murray. The Brit says he will take a call on his Australian Open participation by "the weekend".

Hey everyone.. Just wanted to write a little message on here for anyone interested in what in going through right now. Firstly I want to apologise to @brisbanetennis for withdrawing at late notice and to everyone who wanted to come along to watch me play(or lose?) The organisers couldn't have been more understanding and supportive and I'll always remember that. Thank you. I've obviously been going through a really difficult period with my hip for a long time and have sought council from a number of hip specialists. Having been recommended to treat my hip conservatively since the US Open I have done everything asked of me from a rehab perspective and worked extremely hard to try get back on the court competing. Having played practice sets here in Brisbane with some top players unfortunately this hasn't worked yet to get me to the level I would like so I have to reassess my options. Obviously continuing rehab is one option and giving my hip more time to recover. Surgery is also an option but the chances of a successful outcome are not as I high as I would like which has made this my secondary option and my hope has been to avoid that. However this is something I may have to consider but let's hope not. I choose this pic as the little kid inside me just wants to play tennis and Compete.. I genuinely miss it so much and i would give anything to be back out there. I didn't realise until these last few months just how much I love this game. Everytime I wake up from sleeping or napping i hope that it's better and it's quite demoralising when you get on the court it's not at the level you need it to be to compete at this level. In the short term I'm going to be staying in Australia for the next couple of days to see if my hip settles down a bit and will decide by the weekend whether to stay out here or fly home to assess what I do next. Sorry for the long post but I wanted to keep everyone in the loop and get this off my chest as it's really hurting inside. Hope to see you back on the court soon ??❤️

A post shared by Andy Murray (@andymurray) on

Murray featured in an exhibition match at Mubadala Tennis Championship in Abu Dhabi last month. The three-time Grand Slam champion replaced an injured Novak Djokovic and played a one-set match against Roberto Bautista Agut of Spain.

The Brit ended his season in a bid to recover well from his long-standing hip injury. However, he avoided a surgery and was expected to return at the Brisbane International, from which Rafael Nadal also withdrew, citing issues with his knee.

Notably, he was scheduled to take on USA's Ryan Harrison in the R16 round of the season-opening tournament on Thursday, January 4.

'Disappointed for Andy'

Meanwhile, Brisbane International tournament director Cameron Pearson expressed disappointment at Murray's withdrawal but wished him a speedy recovery.

"I'm really disappointed for Andy [Murray], as I know how much he was looking forward to getting his season started in Brisbane. As a two-time former champion, he has great memories of playing on Pat Rafter Arena and thrilling his fans. I wish him all the best to be ready to play the Australian Open," Pearson said.

Murray, who slipped from the first spot to 16 on ATP rankings in 2017, will have to produce a special effort if he is to reach the final stages of the season's first Grand Slam, provided he gets fit in time.