Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: Andy Murray has faced a tricky transition in recent weeks between hard and clay courts as he tries to balance his preparations for the ATP World Tour Finals at The O2 and the Davis Cup final in Belgium. After four days of training on clay at London’s Queen’s Club this past week, Murray is now back on hard courts as he gets set to open his World Tour Finals campaign against Spaniard David Ferrer on Monday afternoon. Sportsmail was granted the first hit on the freshly-laid court at The O2 as Sky Sports pundit and Murray’s ex-coach Mark Petchey explained the issues involved in changing surfaces which his former charge will have to deal with over the next fortnight.Andy Murray is competing in this week's ATP World Tour FinalsThe world No 2 is also gearing up for the Davis Cup final in BelgiumMurray has flitted back and forth between hard and clay courts recentlyMark Petchey explains the difficulties involved in switching surfacesSee more of the latest news and updates on Andy Murray 
 Question:That again is something he is going to have to contend with during the _.

ATP World Tour Finals