Querrey gives U.S. 2-0 lead in Davis Cup quarters

   San Francisco native Sam Querrey defeated Ruben Bemelmans 6-1, 7-6 (5), 7-5 today in Nashville, Tenn., to give the United States a 2-0 lead over Belgium in the Davis Cup quarterfinals.
   The 6-foot-6 (1.98-meter) Querrey, ranked 14th, pounded 21 aces and won 83 percent of the points on his first serve (45 of 54).  Bemelmans, ranked 110th, had nine aces and nine double faults.
   Earlier, ninth-ranked John Isner beat No. 319 Joris De Loore 6-3, 6-7 (4), 7-6 (8), 6-4. The 6-foot-10 (2.08-meter) Isner, who won the biggest title of his career on Sunday in Miami, hammered 43 aces and won 84 percent of the points on his first delivery (74 of 88).
   Both De Loore and Bemelmans have played in Northern California in recent years.
   De Loore, 6-foot-3 (1.91 meters) and 190 pounds (86 kilograms), ousted top-seeded Bjorn Fratangelo in the first round of the $100,000 Stockton Challenger in 2016 before losing to eventual runner-up Noah Rubin. The following week, De Loore reached the semifinals of the $100,000 Fairfield Challenger.
   Bemelmans, a 6-foot (1.83-meter) left-hander, won the $25,000 Burlingame Futures in 2016 and lost as the first seed in the opening round of the $100,000 Tiburon and Stockton Challengers last fall.
   Belgium, the Davis Cup runner-up in 2015, is playing without veterans David Goffin, ranked 10th, and Steve Darcis, ranked 143rd after reaching a career-high 37th last May, because of injuries.
   The United States can advance to the semifinals for the first time since 2012 with a victory in Saturday's doubles match (2 p.m. PDT, Tennis Channel).