Japan's soon-to-retire former world No. 4 Kei Nishikori advanced to the second round of qualifying for the U.S. Open on Tuesday by beating Sebastian Ofner of Austria 6-1, 2-6, 6-2.The 2014 U.S. Open runner-up and first Japanese player to reach a Grand Slam final is aiming to appear in the main draw of a major for the last time, having announced in late April that he will retire at the end of the season."Winning a match makes me happiest after all," said the 36-year-old, competing at Flushing Meadows as a qualifying wild card.The veteran stormed to win the first set before Ofner fought back …READ FULL ARTICLE