Flavia Pennetta produced an upset in the BNP Paribas Open semi-finals by beating top seed Li Na 7-6 6-3 at Indian Wells.

Below-par displays from both players in the first set brought eight breaks of serve in the opener, but the pair could not be separated and a tie-break was required.

Pennetta claimed the upper hand in the tie-break and edged ahead of Li before securing a 7-5 success to earn the advantage in the contest.

Li, who beat her Italian opponent on the way to winning the Australian Open title earlier this year, found a break of serve early in the second set to put pressure on the 20th seed.

However, Pennetta refused to fall behind for too long as she took full advantage of Li's failures on her serve to move closer to victory.

After taking control, the 32-year-old played with confidence to serve out the match and set up a final against Agnieszka Radwanska.