<table> </table> NEW YORK | So little to separate them over their careers, so little to separate them on this night.</p><p>Serena Williams barely got the better of older sister Venus Williams in a U.S. Open quarterfinal that was fit for a final, coming back in each set to win 7-6 (8-6), 7-6 (9-7) Wednesday night and break a tie in their head-to-head series.</p><p>Down 5-3 in the first set and 5-2 in the second, Serena &#8212; as little sisters are wont to do &#8212; refused to go away and let Venus have her fun. Serena saved two set points in the first set and eight in the second, all in the two tiebreakers Serena somehow survived after long minutes of dangling over the abyss.</p><p>&#8220;It definitely felt like a final of the U.S. Open,&#8221; Serena said. &#8220;I can&#8217;t believe I won. Wow.&#8221;</p><p>In the end, they were separated by three total points, 101-98. Venus had an 8-7 edge in aces. Both double-faulted five times. Both broke serve twice.</p><p>Their quarterfinal tussle in a buzzing Arthur Ashe Stadium, on the heels of their high-quality Wimbledon final in July, seemed to reinforce a sense that the women&#8217;s game continues to operate on Williams Standard Time a decade after older sister Venus appeared on the pro scene.</p><p>This is hard for the sisters, especially in the quarterfinals. Neither of their parents, who also serve as their coaches, were sitting in the guest boxes.</p><p>&#8220;I try not to look at her, because if I look at her, I might start feeling sorry,&#8221; Serena told the crowd afterward. &#8220;I want the best for her. I love her so much. She&#8217;s my best friend.&#8221;</p><p>The crowd of 23,763 also had a hard time figuring out which Williams to support. When Venus missed a backhand wide on the match&#8217;s first point, there wasn&#8217;t a sound &#8212; no applause, no yelling, no booing. Nothing.</p><p><hr class="infobox-hr-separator" /> <div class="infobox"> &#8226;<strong>REVIVAL</strong>: Just a couple of days after she was fearful she had nothing left in her tank, sixth-seeded Dinara Safina overpowered No. 16 Flavia Pennetta 6-2, 6-3. She&#8217;ll face Serena Williams in the semifinals. It is Safina&#8217;s first semifinal at the U.S. Open. She has won 37 of her last 41 matches and made it to the finals at six of her last seven tournaments. Safina won 25 of 30 first-serve points in the win.</p><p>&#8226;<strong>TWIN WIN</strong>: Bob and Mike Bryan reached the finals of the men&#8217;s doubles, beating Tommy Robredo and Sergio Roitman 6-2, 6-1. </p><p>&#8226;<strong>OLD FRIENDS?</strong> The fireworks that flared during the Italian Open in May didn&#8217;t recur when Andy Murray beat Juan Marti del Potro 7-6 (7-2), 7-6 (7-1), 4-6, 7-5 Wednesday afternoon. They put their arms around each other at the net rather than firing tennis balls at each other as they did in Rome. Murray&#8217;s win ended a 23-match winning streak by del Potro during which he won four straight tournaments and rocketed up the rankings.</p><p>&#8226;<strong>WEATHER PLANS</strong>: Long-range forecasts call for Tropical Storm Hanna to curve along the U.S. Atlantic coast this weekend, and officials were huddling to discuss different scenarios. Saturday&#8217;s schedule calls for both men&#8217;s singles semifinals in the afternoon with the women&#8217;s title match on Saturday night &#8212; which rain could interrupt.</p><p>&#8226;<strong>INJURY PRONE</strong>: Andy Roddick had a little fun at the expense of No. 3 seed Novak Djokovic, whom he plays today. Djokovic called for a trainer in his last match, though it wasn&#8217;t clear which ankle was hurting. &#8220;Isn&#8217;t it both of them?&#8221; Roddick asked, rhetorically. &#8220;And a back &#8230; and a hip &#8230; and a cramp &#8230; bird flu &#8230; anthrax. SARS, common cough and a cold. You know, he&#8217;s either quick to call a trainer or he&#8217;s the most courageous guy of all time.&#8221;</p><p></div>