Kathleen Horvath peered over the railing high above the indoor courts at the Billie Jean King National Tennis Center. Outside, rain was pouring down so hard that it sounded as if the New York Philharmonic’s percussion section were rehearsing on the roof.
Horvath tried to pretend she was not sneaking peeks at her 16-year-old son R J Fresen. He was hitting with Julia Elbaba, a four-time all-American at Virginia and a fledgling pro, under the watchful eye of Jay Devashetty, a coach for the United States Tennis Association.
Fresen, once ranked in the top 10 by the U.