How about that for a breakout moment? Learner Tien, the young American lefty, just stunned the tennis world by taking down Medvedev in straight sets at the Australian Open! At only 20, Tien is still living at home, but he’s now in the quarters and set to face Zverev next. Can he keep this Cinderella run going? The USA is making noise down under! #Sports #Tennis #LearnerTien