Jonas Bjorkman and Max Mirnyi, the tour's No. 1 doubles team, are playing in the RCA Championships. Just not in doubles.
The 33-year-old Bjorkman is taking time off to concentrate on singles.
"It's purely because I've dropped my rankings in singles a little bit," said Bjorkman, whose ranking has fallen to No. 105. "I want to do everything I can (to improve it) before it's too late. I've been hitting the ball really, really well."
Bjorkman captured the 1997 RCA singles title and has lost in the doubles final twice.