The Chinese player faces the world number two in the semi-finals of the Australian Open and has lost in eight of their previous 12 meetings.
Rodriguez, who replaced Li's husband as her coach in July last year, said that Li has all the tools to defeat the Russian, who has dropped just nine games on her way to the last four in Melbourne.
"Now she has to believe a little bit more that she can do it," said Rodriguez. "I am convinced that she has the game.
"The main thing is first of all to believe in her tennis and her possibilities to go through the semi-final which is very difficult.
"Most of my work, more than 90% of my job in the last 48 hours is on that."
Li won the French Open in 2011.