Nadal has spent the last four months on the sidelines with a foot injury while he also struggled with back issues at the start of the year.
The 35-year-old Spaniard was knocked out at Roland Garros in the semi-finals before he was forced to pull out of Wimbledon, the Tokyo Olympics and the U.S. Open. He last competed in August at the Citi Open in Washington.
"I am feeling better, if not I will not be here. That's the goal, I know the comeback will not be easy," Nadal told reporters.