Kwiatkowski tops third-seeded Giron in $108K Tiburon

   In a matchup of former NCAA singles champions, 14th-seeded Thai-Son Kwiatkowski of Charlottesville, Va., outlasted third-seeded Marcos Giron of Thousand Oaks in the Los Angeles area 4-6, 7-6 (3), 6-4 today to reach the quarterfinals of the $108,320 First Republic Tiburon Challenger at the Tiburon Peninsula Club.
   Kwiatkowski (University of Virginia) and Giron (UCLA) won the NCAA singles crown in 2017 and 2014, respectively.
   Kwiatkowski improved to 2-0 against Giron, also winning 6-4 in the third set in the first round of qualifying in Fairfield, Calif., last October.
   Also losing today were fifth-seeded Mikael Torpegaard of Denmark, seventh seed and 2016 Tiburon champion Darian King of Barbados and 10th-seeded Christopher Eubanks of Atlanta.
   Gonzalo Escobar of Ecuador toppled Torpegaard, a former Ohio State All-American, 6-4, 7-6 (9). Torpegaard reached the 2018 NCAA singles quarterfinals and doubles final with Martin Joyce.
   Sekou Bangoura of Bradenton, Fla., eliminated King 1-6, 6-4, 6-0 after knocking off 12th seed and 2013 Tiburon champion Peter Polansky of Canada on Wednesday. Polansky, 31, won last week's $54,160 Columbus (Ohio) Challenger on an indoor hard court.
   Wild card Brandon Nakashima, a Virginia sophomore from San Diego, surprised the 6-foot-7 (2.01-meter) Eubanks 7-6 (5), 7-5 one day after ousting sixth seed and defending champion Michael Mmoh.
   Only three of the top 13 seeds reached Friday's quarterfinals. Advancing were top-seeded Tommy Paul of Greenville, N.C., fourth-seeded Emilio Gomez of Ecuador and eighth-seeded Thanasi Kokkinakis of Australia.
   Gomez's father, Andres Gomez, won the 1990 French Open. Kokkinakis stunned Roger Federer last year in Miami.
   Here are the updated Tiburon singles and doubles draws and Friday's schedule.