Andy Murray has split with coach Ivan Lendl for a second time.
The British number one announced the parting of ways on his official website, describing the move as "mutual".
Murray has won all three of his Grand Slam crowns under the guidance of Lendl, winning a second Wimbledon title in the second instalment of their partnership.
But in a statement on Friday, Murray said: "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.
"My focus now is on getting ready for Australia with the team I have in place and getting back to competing."
That quote suggests a replacement for Lendl appears unlikely before the new season, with Jamie Delgado already on his team and fulfilling a number of coaching duties.
Sky Bet are offering 11/10 for Murray to win any of the four Grand Slam singles titles in 2018.
Murray and Lendl did not work together face to face much at all in 2017, although much of that was due to the 30-year-old's hip injury which meant he did not play after Wimbledon.
Lendl said: "I wish Andy well going forward. We had a great run and a lot of fun."
Murray is planning to return to action in Brisbane ahead of the Australian Open in January. However, he has also said he will not play again until he is "100 per cent ready".
Before then he will spend time in Miami for his regular pre-season training block.
Lendl initially became Murray's coach at the start of the 2012 season and is largely credited with getting him over the Grand Slam winning line. Having lost in his first four Grand Slam finals, Murray finally broke his duck at the US Open nine months after appointing Lendl. He also won Olympic gold in that period.
The pair went their separate ways in March 2014, by which time Murray had added a Wimbledon title to his trophy collection.
Murray then appointed Amelie Mauresmo as his coach but he reunited with Lendl in the summer of 2016, the Scot winning in SW19 for a second time just a few weeks later.
