Ros Nideffer and Nathalie Herreman-Bagby, two former touring tennis professionals, won semifinal matches in the 50s singles division and will face each other in the finals of the USTA National Women’s 50-90 Hard Court Championships on May 14 at 10:30 a.m. at the La Jolla Beach & Tennis Club. Nideffer, the top-seed and two-time defending champion, needed only 61 minutes to breeze past fourth-seeded Anna Zimmermann of Indianapolis 6-0, 6-1 on Court No. 2. Nideffer got off to a fast start, losing only six points in the first set, which took 23 minutes. Nideffer, of Rancho Bernardo, was ranked as high as No. 15 in the Women’s Tennis Association singles rankings in 1990. She is a former French Open doubles champion and two-time Wimbledon singles quarterfinalist. On May 14, Nideffer will attempt to win her third straight USTA 50s Hard Court title and fourth overall. She won her first 50s title in 2012 and did not enter in 2013. Herreman-Bagby, 50, of Pacific Palisades, Calif., seeded second, advanced to the final after winning her semifinal match, but it wasn’t easy, as she needed two hours and 32 minutes to overcome third-seeded Judy Newman of Scotts Valley, Calif., 6-2, 4-6, 6-3. Herreman-Bagby was ranked as high as No. 42 in the WTA singles rankings in 1986. A former member of the French Fed Cup team, Herreman-Bagby reached the fourth round at Wimbledon in 1990 and has one career WTA singles title and two doubles crowns. The 44th annual Men’s Senior Championships is also taking place in conjunction with the women’s events and includes both singles and doubles for 60 and over, 65 and over, 70 and over, 75 and over, and 80 and over age groups. Although the men’s events are not national championships, they will feature many senior players who regularly compete in national tournaments. Participation for both the men’s and women’s tournaments is expected to total more than 300 players. For more, see ljbtc.com.