15-Year-Old Qualifier Marta Kostyuk Reaches Third Round of Australian Open Embed from Getty Images (January 17, 2018) Last year’s Australian junior champion Marta Kostyuk, ranked No. 521 in the world came through the qualifying and is now in the third round of the first major tennis event of the year. The 15-year-old Ukrainian followed up her upset win over 25th seed … [Read more...] about 15-Year-Old Qualifier Marta Kostyuk Reaches Third Round of Australian Open