Tomas Berdych's chances of featuring at the ATP World Tour Finals have been scuppered by a persistent back injury.
The Czech is 14th in the rankings and was in with a shot of returning to the event after a run of six successive appearances ended last year.
However, in a bid to begin 2018 in the best shape possible, Berdych has decided to curtail his campaign prematurely.
"I am sorry to let you know that I am forced to call the season off," he wrote in a statement posted on Twitter.
"I have been playing matches with back pain since Wimbledon and in my last match in Beijing I felt like it was not getting better, and I was advised by my medical team to give it a few weeks of rest, and to have treatment, in order to be completely healthy and pain free and to be ready to compete at the start of 2018.
"I am sorry that I won't be able to compete in Vienna and Paris, but I really think it's best for me to be ready and healthy for the January tournaments and the Australian Open, which is one of my favourite tournaments."