Given how long Serena was out with her injured knee -- eight months after last year's Wimbledon -- this is as important a tournament as she'll ever play.
If she loses at Wimbledon this year, she won't be a holder of a major title for the first time in the past couple of years.
With her sister Venus knocked out early, however, Serena stepped up her determination. This will be the first time she could win Wimbledon and feel the full satisfaction of that moment. The two times she won The Championships previously, she had to defeat her sister to do it and her celebrations were subdued.
It seems that Serena doesn't listen to the criticism of all of her outside activities, yet in this season's European swing at the French and Wimbledon, she's vectored in and focused.
Serena Williams (1), United States, vs. Amelie Mauresmo (4), France
It looks like Serena's on one of those rolls in the second week of a major, which she's already won. She looks determined. Given how her play has improved, she's unlikely to take a step backward at this point.
Even though Mauresmo has a lot of athleticism and a variety of all-court tricks, Serena is just on top of her game. When she's that way she's the best in the world.
Maria Sharapova (13), Russia, vs. Lindsay Davenport (5), United States
This matchup is fascinating for a lot of reasons. Davenport is trying to go out with one more major victory, while Sharapova is in her first semifinal of a major. Sharapova is looking determined to be here many, many more times in her career and looking to go further than a semifinal appearance. Both players have special motivations tugging at them and a desire to go further.
This is going to be the more competitive of the two semifinals. Based on Davenport's play so far, she should be able to pick on Sharapova's forehand side in this semifinal. Davenport has too much power on her backhand and serve. She'll be too tough for Sharapova.
If Davenport could win two more matches, it would be a mini-version of what Pete Sampras did at the 2002 U.S. Open because it's been four and a half years since Davenport won her last major. She's certainly the sentimental pick. She's married now and has a strong desire to start a family not too far down the line. Still, even if she wins this round, getting that title might prove elusive.
An upside is that regardless of the outcome of this semifinal, Sharapova's star will continue to rise, and it's the brightest of the teenagers out there.
ESPN tennis analyst Pam Shriver won 21 singles and 112 doubles crowns, including 22 Grand Slam titles.