Andy Murray is set to miss this year's World Tour Finals if, as expected, Belgium decide to host the Davis Cup final against Great Britain on clay.
The Flanders Expo Arena in Ghent will stage the tie if the Davis Cup Committee gives its approval on Tuesday.
The Belgian Federation has two weeks to confirm its choice of surface, but has opted for clay in four of its last six home ties and may conclude it is the surface most likely to inconvenience Murray.
The World Tour Finals - on a hard court - finish at London's O2 Arena on Sunday, 22 November, with the Davis Cup final played over three days from the following Friday.
"The O2 would obviously be a question mark for me if we were playing on the clay," Murray told BBC Radio 5 live after sealing Britain's place in the final.
"I would go and train and prepare on the clay to get ready for the final.
|Andy Murray's ATP Finals results|
|2014: Round robin|
|2013: Did not play|
|2011: Round robin|
|2009: Round robin|
"You saw last year with Roger Federer that the matches at the O2 are extremely tough and physically demanding.
"If you reach the final and play on the Sunday you also need to take time off - you can't just play five matches against the best players in the world and then not take any days off."
Federer woke up with a bad back on the morning of last year's final at the O2 and was unable to play Novak Djokovic.
Although Switzerland went on to win the Davis Cup the following week, Federer lost his opening match to France's Gael Monfils in straight sets.
Murray's back surgery in 2013 was successful, but he was managing a problem throughout Britain's semi-final victory over Australia and needs extra time to make the transition to clay.
The Scot, who won three points in the 3-2 win over Australia in Glasgow, explained: "For me to play - if I was to reach the final - five in a row and then take a couple of days off, it would mean only playing for two days on the clay before the Davis Cup final starts and that wouldn't be enough for me.
"I need more time on the clay to let my back get used to it."
|Belgium thrashed in sole final|
|Belgium have only played in the Davis Cup final on one previous occasion - in 1904, when they were beaten 5-0 by Great Britain.|
If Murray does not play in the World Tour Finals, he will miss out on prize money ranging from £100,000 to £1.25m, 1,500 ATP ranking points and the chance to win the prestigious season-ending event for the first time.
The Flanders Expo Arena, meanwhile, which in the past has hosted Elton John, Prince and U2, as well as Belgian TV's version of The Voice, will have a capacity of 13,000 fans for the final. Although the arena is vast, the height of the roof limits the size of the stands that can be built.
Tickets are expected to be cheaper than for last year's final which was watched on the opening day in Lille by a world record crowd of more than 27,000 people.
However, it is unlikely there will be more than 1,300 made available to British fans with the Belgian Federation only obliged to distribute 10% to the away team and Belgium appearing in their first Davis Cup final for 111 years.
Murray 'expected to play' in London - ATP
Chris Kermode, executive president of the ATP which governs men's professional tennis, said Murray would be expected to play in London.
"The Barclays ATP World Tour Finals is a mandatory event on the ATP World Tour," he said.
"All players who qualify, unless injured, are required to compete in the event. Andy Murray has had a fantastic season and earned his place among the world's top eight players to compete at the season finale.
"We are aware of the comments made after the Davis Cup tie in Glasgow, however our expectations are that, if fully fit, Andy would compete in this year's tournament. Unless we hear otherwise via an official withdrawal, he is still entered to compete at the O2."