Roger Federer on Sunday withdrew from next week's Paris Masters after suffering a 6-4, 6-7 (5/7), 7-6 (7/3) final loss to Juan Martin del Potro at the Swiss Indoors.
The world number one revealed his late decision to skip the event he won a year ago as part of a sweep of the last three events of the 2011 season.
Federer, 31, said he felt he needed to let a few niggles heal to be fully fit for the start of the World Tour Finals in London a week from Monday.
"I'm not going to Paris, it's too much for me," said Federer. "I've already told (tournament director) Guy Forget. I have some niggling stuff that I want to heal, I don't want to take a chance for London.
"I tried to make up my mind yesterday and again today. I need some time to prepare properly for London.
"In a way, missing Paris is disappointing. I remember how great it was to win the title a year ago. I had one of the best weeks of my life there in 2011.
"I don't want to mislead anyone, but this was a very last-minute decision. But it was the only right decision for me if I want to play a good London."