Andy Murray is performing a delicate balancing act as he prepares for a claycourt Davis Cup final and the ATP World Tour Finals on an indoor hardcourt at the O2 Arena.
The Scot, who has prioritised helping Britain win the Davis Cup for the first time since 1936 when they face Belgium in Ghent later this month, will spend most of this week practizing on clay in London.
The Tour Finals, where Murray can clinch the year-end number two ranking for the first time, begin on Sunday, meaning a testing few days for the 28-year-old.
The transition to the specific movements of claycourt tennis have proved problematic in the past for Murray who has often suffered back pain as a consequence.
"I've tried to juggle the two so that I don't have to miss the (Tour Finals) but also give myself a good chance of playing well in the Davis Cup," said Murray who was beaten in the Paris Masters final on Sunday by Novak Djokovic.
"It's important I'm not too hard on myself and don't just expect to play great tennis at the start at the O2 as soon as I switch back to hardcourts.
"I need to respect what the change to the clay can do to my body and also what it can do to your game because it's a completely different movement."
When Britain beat Australia in September to reach the final for the first time since 1978, Murray winning all his three matches, the Scot indicated he might miss the ATP finale that features the world's top eight players.
He now says he could still pull out if he is worried about his fitness for the Davis Cup final that starts on Nov. 27.
"It's going to be tricky," added Murray. "If I get injured in the next couple of days or something happens to my back then obviously I won't play (at the O2).
"But if I'm fit and healthy and the next three days go well well then I'll be practising at the O2 from Friday."
Twice grand slam champion Murray has never won the ATP's season-ender.