The Scot, who has still not hit the court while there are ranking points to play for since Wimbledon 2017, had been due to return to action in Queensland this week with a second round match against Ryan Harrison of the USA.
However, the hip injury which terminated his 2017 season prematurely appears still to be hampering his fitness.
“I’m very disappointed to be withdrawing from the Brisbane International. I came here 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.
“I have grea...
Their coaching partnership over two separate periods marked a very successful time for the Brit, in which he won three slam titles and two Olympic Golds, as well as reaching world No. 1 last year.
Murray described the split as being by mutual agreement.
"I’m thankful to Ivan for all his help and guidance over the years, we’ve had great success and learned a lot as a team," Murray said.
"My focus now is on getting ready for Australia with the team I have in place and getting back to competing.”
Lendl added: "I wish Andy well. We had a great run and a lot of fun."
Murray, who has been out of action with a hip injury, will continue to buil...
In a post on his Instagram account, Murray definitively ruled out his participation in the upcoming Asian swing events in Beijing and Shanghai, before strongly hinting that he would also miss the indoor events in Vienna and Paris that close out the regular season.
Murray won each of these events in 2016, as part of the blistering run of form that swept him to the world number one ranking by the end of the year.
After a 2016 with so many high points for Murray, 2017 has seen a cruel reversal of fortunes as he battled a dip in form, illness and injury.
The world number two was hampered by the injury at Wimbledon and has not played since.
Although Murray travelled to New York and practised on site, he made the decision to withdraw from the tournament.
"It's too sore for me to win the tournament and ultimately that's what I was here to try and do," said Murray in a press conference.
"I did pretty much everything that I could to get myself ready here and took a number of weeks off after Wimbledon," added Murray.
It is not yet clear whether Murray will play again in 2017.
The tournament has been hit by a number of high-profile withdrawals – as well as Murray, Novak D...
Murray’s hip has been the subject of fierce debate throughout these championships. The Scot had done his best to hide the extent of the injury. But there was no disguising it today, as he hobbled between points and leant on his racket.
Murray started brightly enough, taking the first eight points. The top seed consolidated that break to take the first set 6-3.
At 3-3 in the second set, a double-fault from Querrey followed by a crosscourt backhand and a drilled pass down the line from Murray earned a break of serve. The Scot seemed set fair for an e...
The serve is usually dominant on grass, but four breaks were exchanged in an enthralling opening set. Paire is an unorthodox player, and his variety initially caused Murray problems. Booming groundstrokes were interspersed with delicate volleys, the occasional drop shot and plenty of unforced errors.
The Brit eventually found some rhythm and galloped through the tiebreak before opening up a 2-0 lead in the second set. Paire broke back to level the score at 3-3, but Murray broke again for a 5-4 lead. The Brit wobbled serving for the set, but defended four break points before finally getting over the line.
Andy Murray: the Man in the Arena