Teenage sensation Amanda Anisimova blew defending champion Simona Halep out of the French Open 6-2, 6-4 in a quarterfinal shock on Thursday, setting her sights on the Suzanne Lenglen Cup in a wide open draw. American teen now takes on Australian eighth seed Ashleigh Barty in the semifinals. Barty saw off 14th seed Madison Keys 6-3, 7-5 to also become a first-time Grand Slam semifinalist. Third seed Halep, who had been looking to become the first woman to retain her title at Roland Garros since Belgian Justine Henin won three times in a row from 2005-07, never found a solution to counter the 17-year-old American's beguiling mix of speed and accuracy. The unseeded Anisimova, the first player born in the 2000s to reach the last eight at a Grand Slam, can become the first teenager to lift the trophy here since Iva Majoli of Croatia prevailed in 1997. "This is honestly more than I could ever have asked for," Anisimova, who won her first career title at tour-level on the Bogota clay in April, said on court at the finish. "That was one of the best matches I have ever played. "Going out there today, I knew that if I wanted it I had to give something different." Anisimova got off to a canon start, playing fearlessly to open a 4-2 lead with the first break, and then steal Halep's serve again to bag the opening set in under half an hour. With balls leaving her racket at bullet speed, Anisimova kept the pressure on, sometimes drawing her opponent to the net before finishing off the point with passing shots. In a half-empty stadium, ticket holders having opted for an early lunch before the men's semi-final between Novak Djokovic and Alexander Zverev, a few 'Simona, Simona!' chants came down from the stands as Halep finally won a game having lost seven in a row. Anisimova was 3-1 up and Halep had break points, only for the American to see them off, finding unpredictable angles that left the Romanian often unbalanced. But Halep broke back in the seventh game when Anisimova overplayed a backhand down the line. The teenager showed signs of nerves at 4-4 but Halep failed to convert a break point and her failed efforts to get back into the contest proved costly as Anisimova wrapped it up with her 25th winner. Barty reached her first Grand Slam semifinal as she outplayed error-prone American Keys on Thursday. In a quarterfinal clash postponed on Wednesday because of heavy rain, Barty produced an intelligent display full of guile in the Court Suzanne Lenglen sunshine. Barty's greater variety proved too much for 2018 semifinalist Keys whose power game broke down at the vital moments. A reflex backhand winner gave 23-year-old Barty the decisive break when Keys served at 3-4 in the first set. Using her clever changes of pace, she provoked errors from the powerful Keys to break again at 3-3 in the second. Serving for the match at 5-4 Barty wavered for the first time in the match, double-faulting and then netting a forehand on break point to hand Keys a way back into the match. But the respite was shortlived. Keys dropped serve with a double-fault in the next game and this time Barty sealed victory. "Anisimova has been playing some great Tennis, to reach a semifinal you must be doing the right things," Barty, who once quit Tennis to play cricket, said on court. "It's an exciting opportunity for both us and we will both enjoy it tomorrow." — Reuters