Andy Murray has withdrawn from next month's ATP World Tour Finals in London as he continues his recovery from back surgery.
World number three Murray had an operation last month and Wednesday saw the two-time Major winner confirm what had long been suspected when he announced he wouldn't be fit to play in the showpiece event.
"I'm really disappointed not to be playing this year, I love playing in front of my home crowd, it's a great atmosphere," Murray told atpworldtour.com.
"All the players look forward to competing in London and I'll be doing my best to qualify again for the tournament next year."
The 26-year-old Scot started struggling with the back problem during the 2012 clay-court season and it recurred at around the same time this year, forcing him to miss the French Open.
But his absence from Roland Garros helped him compete at Wimbledon where he became the first British man in 77 years to win the men's singles title.
However, while fit enough to get through a fortnight on the grasscourts in London, Murray was still not at the absolute peak of fitness and the subsequent defence of his US Open title saw him suffer a surprise quarter-final defeat by Stanislas Wawrinka.
However, it has been reported that Murray's recovery is on schedule and that he he will be fit to play as scheduled in a Barbados exhibition event in November and the Abu Dhabi tournament towards the end of December.
London event director Andre Silva, commenting on Murray's withdrawal, said: "It's unfortunate that Andy will be unable to play in this year's tournament.
"He's had a historic year on the Tour and of course he'll be missed. We wish him all the best as he continues his recovery from surgery and we hope to see him back stronger than ever for the 2014 season."
Rafael Nadal, Novak Djokovic and David Ferrer have already qualified for the event, which features the best eight players of the year.
Juan Martin del Potro and Tomas Berdych are closing in but the next four weeks could see a tight battle for the remaining places at the Tour finals, which are staged indoors at London's O2 Arena.
Roger Federer, Wawrinka and Richard Gasquet currently occupy seventh, eighth and ninth positions, but Milos Raonic and Jo-Wilfried Tsonga could yet overtake them.