Sofia Kenin knocked out No. 3 seed Ekaterina Alexandrova 6-0, 2-6, 7-6 (3) on Friday to advance to the Toray Pan Pacific Open semifinals in Tokyo. Kenin trailed 5-2 in the deciding set and fought off four match points to force the tiebreak, withstanding a dozen aces by the Russian to win in two hours and 17 minutes.