Andy Murray may skip this year's World Tour Finals in order to prepare for Great Britain's Davis Cup final against Belgium in November.
Murray inspired Britain to victory over Australia in the Davis Cup semi-finals, securing their first appearance in a final since 1978 with a straight-sets win over Bernard Tomic in Glasgow on Sunday.
Belgium are expected to stage the final on clay and with the hard-court World Tour Finals not due to finish until the week before, Murray is thinking about sitting out the prestigious event at London's O2 Arena.
"The O2 would obviously be a question mark for me if we were playing on the clay," Murray, a two-time World Tour Finals semi-finalist, said.
"I would go and train and prepare on the clay to get ready for the (Davis Cup) final. 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."
Missing the World Tour Finals would oblige Murray to forego 1,500 ATP ranking points.
His 7-5, 6-3, 6-2 victory over Tomic gave Britain an unassailable 3-1 lead, with Thanasi Kokkinakis' win against Dan Evans in Sunday's final singles rubber making the final score 3-2.
Belgium, who defeated Argentina 3-2 in the other semi-final, will host the final on November 27-29.
Murray, 28, won both singles matches as well as the doubles with elder brother Jamie, and revealed afterwards that a back injury sustained in training had dogged him throughout the tie.