Ex-Stanford star shocks No. 2 seed in Aptos

   The $100,000 Comerica Bank Challenger got off to a wild start as all three seeds in action lost.
   Wild card Bradley Klahn topped the list of upsets, stunning No. 2 Igor Andreev of Russia 7-6 (3), 6-4 Monday at the Seascape Sports Club in Aptos, Calif. The tournament site is 80 miles south of San Francisco.
   Klahn, a 21-year-old left-hander from the San Diego suburb of Poway, turned pro last month after completing his eligibility at Stanford. He won the 2010 NCAA singles title.
   Andreev is ranked 95th in the world after reaching a career-high No. 18 in 2008. The 29-year-old veteran advanced to the quarterfinals of the 2007 French Open.
   Meanwhile, No. 7 Izak Van der Merwe of South Africa lost to Amir Weintraub of Israel 6-4, 7-6 (1), and and No. 8 Denis Kudla, 19, of Arlington, Va., fell to Rik de Voest of South Africa 6-2, 6-2. De Voest, 32, won the inaugural Sacramento Challenger in 2005.
   Longtime Sacramento-area resident Dmitry Tursunov, seeded first in qualifying, advanced to the main draw with a 6-1, 6-3 triumph over seventh-seeded Daniel Kosakowski of Downey in the Los Angeles area. Kosakowski won last year's Sacramento Futures after his freshman year at UCLA, then turned pro.
   Tursunov, a Russian who reached a career-high No. 20 in 2006, will meet third-seeded Rajeev Ram of Carmel, Ind., today at about 2 p.m.  
    Top-seeded Brian Baker of Nashville, Tenn., will face Maxime Authom of Belgium in the opening round today at 5:30 p.m. or later. 

CALENDAR

   Through Thursday -- USTA National Championships, girls 14s, Peachtree City, Ga.., www.usta.com.
   Through Friday -- USTA National Championships, boys 14s, San Antonio., www.usta.com. 
   Through Friday -- USTA National Championships, boys 12s, North Little Rock, Ark.., www.usta.com.
   Through Friday -- USTA National Championships, girls 12s, Alpharetta, Ga., www.usta.com. 
   Through Sunday -- USTA National Championships, boys 18s and 16s, Kalamazoo, Mich., www.usta.com. 
   Through Sunday -- USTA National Championships, girls 18s and 16s, San Diego., www.usta.com.
   Through Sunday -- $100,000 Comerica Bank Challenger, Seascape Sports Club, 1505 Seascape Blvd., Aptos, Calif., 95003, www.seascapesportsclub.com/challenger, (831) 688-1993.
   Aug. 27-Sept. 9 -- U.S. OPEN, Flushing Meadows, N.Y., www.usopen.org.
   Sept. 9-16 -- $25,000 USTA Oak River Rehab Challenger, Sun Oaks Tennis & Fitness, 3452 Argyle Road, Redding, Calif., 96002, www.sunoakschallenger.com, (530) 227-3498.
   Sept. 14 -- World TeamTennis, Western Conference finals, Sacramento Capitals vs. Orange County Breakers, 3:30 p.m. PDT, Charleston, S.C.
   Sept. 15 -- WTT, Eastern Conference finals, Washington Kastles vs. New York Sportimes, 3:30 p.m. PDT, Charleston, S.C.
   Sept. 16 -- WTT Finals, Western Conference champion vs. Eastern Conference champion, 12:30 p.m. PDT, Charleston, S.C.
   Sept. 29-Oct. 7 -- Natomas Men's $100,000 Challenger, Natomas Racquet Club, 2450 Natomas Park Drive, Sacramento, Calif., 95833, www.natomaschallenger.com, (916) 649-0909.
   Oct. 6-14 -- First Republic Bank Men's $100,000 Challenger, Tiburon Peninsula Club, 1600 Mar West St., Tiburon, Calif., 94920, www.tiburon challenger.com, (415) 789-7900.