Tennis great Navratilova quits
When Agnieszka Radwanska announced in December that she had hired her idol Martina Navratilova, it seemed the Polish player was taking a significant step in her bid to win a first grand slam title. Instead, they have parted ways just months into the 2015 season, with the former world No. 2 having slumped from sixth in the rankings to ninth -- reaching only one semifinal, and that in a minor tournament in her home country. Navratilova, an 18-time grand slam singles title winner, said in a statement that she was too busy to continue in her part-time role. Born in the former Czechoslovakia but a longtime U.S. citizen, Navratilova married her partner Julia Lemigova in December. "I think I underestimated the time it would take to make this a proper and good situation for both Agnieszka and me," the 58-year-old said on the WTA Tour website. "I have quite a busy family life now as well as my TV work and other business commitments, which all combined make it impossible to dedic...