U.S. Open Day 12 highlights: Peng succumbs to heat

   Women's semifinals -- Unseeded Peng Shuai of China retired with heat exhaustion and leg cramps while trailing 10th-seeded Caroline Wozniacki of Denmark 6-7 (1), 3-4. Wozniacki, 24, reached her second Grand Slam final; she lost to Kim Clijsters in the 2009 U.S. Open title match.

Serena Williams reached her fourth straight
U.S. Open final. Photo by Paul Bauman

   Top-ranked Serena Williams overwhelmed 17th-seeded Ekaterina Makarova of Russia 6-1, 6-3 to gain her fourth straight U.S. Open final. She lost to Samantha Stosur in 2011 and beat Victoria Azarenka in 2012 and 2013.
   Men's semifinal matchups -- Novak Djokovic (1) vs. Kei Nishikori (10) today at 9 a.m. PDT on CBS. Djokovic leads the head-to-head series 2-1, including a withdrawal by Nishikori in the Miami semifinals in March because of a groin injury.
   Roger Federer (2) vs. Marin Cilic (14) today, after the first semifinal, on CBS. Federer leads 5-0, but their last meeting was close. Federer prevailed 7-6 (5), 6-7 (3), 6-4 early last month in the third round at Toronto.
   U.S. report -- Abigail Spears of San Diego and Santiago Gonzalez of Mexico lost in the mixed doubles final for the second consecutive year. This time, they saved five championship points before falling to top-seeded Sania Mirza of India and Bruno Soares of Brazil 6-1, 2-6 [11-9].
   It was the third career Grand Slam mixed doubles title for Mirza and second for Soares. They played together in a tournament for the first time.
   Three American juniors -- Francis Tiafoe in the boys draw, and Caroline Dolehide and Katerina Stewart on the girls side -- reached the singles semifinals.
   The sixth-seeded Tiafoe, perhaps the United States' greatest male hope, edged top-seeded Andrey Rublev of Russia 6-1, 5-7, 6-4. He will meet fifth-seeded Quentin Halys, a Frenchman who topped fourth-seeded Stefan Kozlov of the United States 3-1, retired.
   Dolehide, a qualifier, surprised fellow American Tornado Alicia Black, seeded fourth, 6-3, 7-5. Stewart, a wild card, demolished unseeded Greet Minnen of Belgium 6-2, 6-0.  
   Northern California connection -- Williams won her third Bank of the West Classic title at Stanford in July.
   Fast fact -- Williams has won her last 20 U.S. Open matches and 38 of her last 40.
   Quote -- Peng, when a doctor checking her on the court suggested quitting: "I said, 'No, no, no. I don't want to give up. I want to try one more time.' "