By HOWARD FENDRICH
AP Tennis Writer
LONDON (AP) — Roger Federer says he was paying attention along with everybody else when Serena Williams played what is expected to be her last match three weeks ago at the U.S. Open. He wasn’t surprised she is moving on from her playing career, just as he is after one last match at the Laver Cup on Friday. He recognizes that their back-to-back exits after about a quarter-century each in tennis will spur some fans to move on from the sport. Federer insists in an interview with The Associated Press that plenty will stick around. That’s because he thinks new superstars will emerge to keep folks interested.