Isner Downs Karlovic to Advance at Hall of Fame Championships
Two-time defending champion John Isner fired 23 aces to cut down fellow big-serving giant Ivo Karlovic and reach the quarterfinals of the 2013 International Tennis Hall of Fame Championships, 7-6(3), 7-6(3). Isner and Karlovic combined to serve 37 aces in their first grass-court meeting ever. Karlovic is playing in his first ATP World Tour tournament since…

