In a topsy-turvy encounter, Riske maintained her composure brilliantly to run out a 6-2, 3-6, 6-0 winner. In the semifinals she will face either Camila Giorgi or Wang Qiang.
? WTA (@WTA) January 5, 2017
"I was just kind of focusing on one point at a time, and I know that's what Aga does - she's there for every single point - so I felt that I had to match her in that regard," Riske said in her post-match press conference. "I also tried to keep my energy high, and I think that I did a good job of that today."
Twelve months ago, Radwanska capped a dominant week with a masterful performance against Riske - then ranked just inside the Top 100 - in a one-sided final. Since then, the American has made steady progress, finishing last year with another final in China and a career-best ranking of No.39.
Her improvements were immediately apparent in the rematch, bossing the exchanges to surge into a 5-0 lead. Radwanska roused herself to register a couple of games before the set's end, then harnessed this momentum to level the match with some typically cerebral tennis.
Riske, though, refused to be stymied for long, calmly dispatching an overhead to break at the start of the decider. From then on, it was one-way traffic as the No.8 seed calmly closed out the biggest win of her career.
"The ultimate goal is to go one better than last year, but I can only look to the next match and I feel if I keep focusing on myself, my game, then who knows what can happen."