BEIJING–Russian teenager Mirra Andreeva pushed through two tie-breaks to beat her compatriot Ekaterina Alexandrova 7-6 (7/4), 7-6 (7/3) at the China Open on Thursday, powering into a semi-final clash with Nikola Bartunkova. Andreeva, the 19-year-old fourth seed, is the favorite for the tournament in Beijing now that a series of upsets have knocked out her