Tracy Austin

I can only guess what it would be like for Richard Williams and Oracene Price, along with the other members of the family, to watch Serena and Venus play. When the sisters walked onto the Arthur Ashe Stadium court a little after 8 p.m. neither Richard or Oracene were present. It was just too tough to be on hand. I was so fortunate that during my career I never had to play my only sister Pam, who is older. I can't think of a more difficult match if I had to play it.

I think tonight's match was very high quality though there were some lulls.

Serena was off at the start of the first set and the same thing happened to Venus early in the second, but overall, it was as good as their Wimbledon final. The intensity was high. They really pushed each other.

Venus had some shots, but she missed a lot of opportunities. Serena dug deeper. She really wanted it and deserved the 7-6, 7-6 win. I think she moved so well, particularly at the end of the second set, that she caused Venus to make errors. The match statistics show that Serena hit 24 winners and made 28 unforced errors. Venus was better with winners, hitting 36, but she made 45 unforced errors and I think this was because Serena was running everything down. Venus failed to convert any of the 10 set points she had because Serena played the crucial points better.

With this performance, I consider her the tournament favorite.

All three of the other semifinalists are playing very well. Dinara Safina, before her last match, talked about being so fatigued that she could barely warm up. She has traveled so much, a lot more than she is used to, but she continues to win. Elena Dementieva has improved her serve. She used to toss the ball so far to the right she could only slice it. Now, she is tossing it in the proper place and can get more topspin on her serve.

That has given her more confidence so she can go after it. Jelena Jankovic was No. 1 for a week without winning and she really wants to prove that she deserved being the top player. She really wants to win a Grand Slam tournament.

This is Serena's 11th event this year and it's the first time she has played all the Grand Slam tournaments in back-to-back years. She has worked very hard to get into and stay in shape. She has been healthy and I think this is very good for women's tennis. With Justine Henin and Kim Clijsters having retired, and Maria Sharapova injured, the Williams sisters have propped up the game. Venus won at Wimbledon and now Serena wants hers.

In the four U.S. Open matches they played prior to their quarterfinal meeting, Venus only gave up three games against her opponents and Serena four. Of all those in the last eight, Serena was on-court the least amount of time, only four hours combined.

She was appearing in her 24th and Venus in her 29th Grand Slam quarterfinal. It was their 17th career meeting (11th at a major), and the 17th time they both had reached the quarters at a Big Four event. Before Wednesday night, they each had won eight times. (Serena was 6-5 in hard court meetings.) It's not surprising, as close as they are, that they each had won three tie-breaks in all the matches they had ever played.

With 15 championships between them, the sisters are the only women left in the tournament who have won Grand Slam tournaments. Even more amazing, in the 62 events they both have played, Serena has won 15 and Venus 13. In the nine finals they have contested, Serena, with six wins, has twice as many victories. Tennis fans, of course, remember their most recent meeting at Wimbledon that Venus won.

MORE FROM TENNIS

Tennis Section Front

Focus on the man Agassi has become   Andre Agassi: ‘I was depressed’   Live vote: Should Agassi return his titles and money? Federer loses in second round of Paris Masters Safin bids farewell to tennis in Paris Gasquet gives cocaine-kiss evidence to CAS hearing   Video: Djokovic or del Potro will win ATP finale   Video: Nadal honored by French officials Interactive: Creating the perfect tennis player ATP, WTA scores, schedules Tennis Section Front   Add Tennis headlines to your news reader: