Li became the first player to take a set off Radwanska this season when she edged a tight first set which saw seven breaks of serve, but she then lost the first two games of the second set to love.[break]
However, Li then rattled off five straight games and saw off two break points when she served for the match at 5-3 to claim her sixth win in 10 meetings with Radwanska.
Radwanska had been on a run of 13 straight wins, including 26 sets unbeaten, after claiming tournament wins in Auckland and Sydney.
Li will face the winner of Tuesday´s all-Russian quarter-final between world number two Maria Sharapova and Ekaterina Makarova in the last four.
Li, a 2011 Australian Open finalist, is now into her first Grand Slam semi-final since she won the French Open in 2011.
Related story
Radwanska, Cibulkova, Li, Kerber into Sydney semis
-1776353206.webp)
