Serena edges Venus in all-Williams US Open quarter, Nadal in semis

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NEW YORK, Sept 4 (AP) Serena Williams watched the final shot sail beyond the baseline, and immediately her sister called for an instant-replay challenge. At that point, Venus Williams really had nothing else to lose. So more than 20,000 fans hushed Wednesday night, looking at the giant video boards high above Arthur Ashe Stadium. A moment later, the call was confirmed and the crowd roared Serena had won this family affair at the US Open.brIt may have been only a quarterfinal, but on the court and in the stands, it sounded as if they were playing for the title as the shrieks and shouts kept getting louder and louder.brI don't think it'll ever be underdramatised until we're housewives, Venus said. Until that time, we'll hopefully keep playing good tennis against everyone and also against each other.brWith a semifinal spot at stake, the sisters who teamed to win the Olympic gold medal in doubles were separated by the slightest of margins. Serena finished ahead in total points 101-98, and most every other number was close.brOnly one stat was out of whack Venus went 0-for-10 on set points, Serena was 2-for-2.brI thought for sure we'd be in three sets, Serena said. I thought, 'I'm going to go change my dress because I'm really sweaty and put a new one on.' And then I was like, 'Oh, maybe I won't have to do that.'brTop-seeded Rafael Nadal worked late into the night - and the early morning - to reach the semifinals at the US Open for the first time in six tries at Flushing Meadows.brIn a match that started at 1130 pm and ended at 210 am, the Wimbledon, French Open and Olympic champion beat unseeded Mardy Fish 3-6, 6-1, 6-4, 6-2. They approached the latest finish in the tournament's history - Mats Wilander defeated Mikael Pernfors at 226 am in 1993 - and moved on to play Andy Murray.brThis is one of the things that we players discuss all the time. There should be a limit on when to start. But we know that the TV rules in this, Nadal said.brI think I'm going to end up sleeping at 5 am. I've got to go eat. With all the attention on the match, it takes a while to unwind. There's nothing else you can do.brSaid Fish It's not ideal starting that late, but I was ready. The first set couldn't have gone better for me.