Sharapova suffers another loss
"It's not been a good end of the season for me," said the 12th seed, who has slipped to 21st in the rankings.
"I have not had good preparations and will have to find away to improve next season."
In contrast, another former world number one, Ana Ivanovic, continued to enjoy her return to some kind of form with a 6-0 7-5 win over Olga Govortsova.
After a miserable couple of years that saw the Serb drop from top of the world rankings to as low as 63, Ivanovic has been slowing improving since joining up with Steffi Graf's former coach Heinz Gunthardt earlier this year.
Next up for Ivanovic will be seventh seed Elena Dementieva, who was given the run around before she overcame 40-year-old Kimiko Date Krumm 6-3 1-6 6-3.
The ninth seed said she was not rattled by the mounting pressure to win the title on home soil.
"It doesn't matter who I play against, be it the top player, an ordinary player, or even a lower-ranked player, I will always believe I have a good chance. The only problem is whether I am able to take that chance," said Li.