Injury prevents matchup of two-time SAP Open champs

   It was going to be a special match for Northern California tennis fans.
   But fourth-seeded Andy Murray received a walkover from 26th-seeded Milos Raonic on Sunday in the third round of the Sony Ericsson Open in Key Biscayne, Fla. Raonic said he had sprained his right ankle in practice. Murray, the 2009 champion, will face 12th-seeded Gilles Simon in the fourth round.   
   Murray, 24, of Scotland and Raonic, 21, of Canada won their first ATP World Tour titles at the SAP Open in San Jose and repeated the following year. Murray, 6-foot-3, broke through at 18 years old in 2006 and Raonic, 6-5, at 20 last year. Sunday's match would have been their first meeting.
   Both players are projected to win Grand Slam singles titles. Murray is 0-3 in major finals; Raonic's best showing in a Slam is the round of 16 as a qualifier in last year's Australian Open. Raonic's progress was slowed by hip surgery last July. 
   Meanwhile, eighth-seeded Mardy Fish received a possible reprieve when 10th-seeded John Isner lost to 19th-seeded Florian Mayer of Germany 6-4, 6-2. Fish -- who plays 28th-seeded Kevin Anderson, 6-8, today in the third round -- is in danger of dropping out of the top 10 and being replaced by Isner as the top American. 
   Fish, 30, is scheduled to play two home matches for the Sacramento Capitals of World TeamTennis on July 12 and 13. He must reach at least the Key Biscayne semifinals, matching his result last year, to avoid falling from No. 8. Isner, 26, lurks at No. 10.
   No. 1 women's seed Victoria Azarenka of Belarus improved to 25-0 this year with a 6-0, 6-2 victory over Heather Watson of Great Britain in the third round. Azarenka won the first nine games.
   In the second round of men's doubles, top seeds and ex-Stanford All-Americans Bob and Mike Bryan defeated Marcelo Melo of Brazil and Juan Monaco of Argentina 6-3, 6-4. The Bryan twins won the doubles crown at Key Biscayne in 2007 and 2008.
   Jean-Julien Rojer, a Netherlands Antilles native and resident who will play full-time for the Capitals in July, and Aisam-Ul-Haq Qureshi of Pakistan lost to Daniele Bracciali of Italy and Juan Sebastian Cabal of Colombia 6-2, 7-6 (7).
   Cal women coast -- The 10th-ranked Cal women (13-4, 5-0 Pacific-12 Conference) extended their winning streak to seven matches with a 7-0 victory over No. 38 Washington State (12-5, 2-3) in Berkeley.