By JEFF WALLNER
MASON, Ohio (AP) — Serena Williams plays Monday night at the Western & Southern Open in what is expected to be one of her final matches. It’s a big deal, even for a U.S. Open tuneup accustomed to hosting the world’s best players. Tournament CEO Katie Haas calls Williams “a global icon whose impact certainly transcends tennis.” The 40-year-old Williams is preparing to walk away from tennis, saying she wants to have another child and pursue business interests. The 23-time Grand Slam champion has not said what her last event will be, but did make it sound as if her final farewell will come at the U.S. Open, which begins Aug. 29 in New York.