Li reaches Indian Wells 4th round
Li Na of China hits a return to Karolina Pliskova of the Czech Republic during the BNP Paribas Open at Indian Wells Tennis Garden on March 9, 2014 in Indian Wells, California - by Stephen Dunn
Li, the world number two and the top women's seed in the California desert, is seeking her third title of 2014.
She lifted the trophy in Shenzhen in her native China before claiming the second Grand Slam crown of her career in Melbourne in January.
Li said she was surprised by 67th-ranked Pliskova's big serve in their first WTA meeting, but she held on to win in one hour and 21 minutes.
She will play the winner of the match between Canadian Aleksandra Wozniak and 21st-seeded Russian Anastasia Pavlyuchenkova.