New generation of U.S. women's tennis?

Serena Williams made it easily through to the third round of the U.S. Open Thursday, dropping a total of three games through two matches. She is joined there by four other American women -- Sloane Stephens, Christina McHale, Irina Falconi and Vania King.

American Women
In Third Round at 2011 U.S. Open

As the Williams Sisters have struggled through injury and illness in the past year -- Stephens, McHale, Falconi and King could represent the next generation of American women's tennis. Each is 22 years old or younger. Each reached the third round by taking out a seeded player, the most impressive win being McHale's upset of eighth-seeded Marion Bartoli.

The last time five American women made it to the third round at Flushing Meadows was in 2004 when eight Americans made it that far, led by eventual semifinalists Jennifer Capriati and Lindsay Davenport.

When it comes to women 22 and under, the last time four or more made the third round at the U.S. Open was in 2000 according to the WTA Tour. That year 20-year-old Venus Williams won her first U.S. Open title, while sister Serena made the quarterfinals.

The play of the four young Americans has been surprising in that for the most part, they have never been here before. The one exception is King who has made the third round in a Grand Slam two previous times (losing both times).

Christina McHale's Keys to the Match
vs Maria Kirilenko, IBM Insights

For Stephens, the only wildcard remaining in the field, this is her second Grand Slam appearance after losing in the first round at this year's French Open. Falconi is playing in her fifth career Grand Slam, but until this tournament had never won a match on the big stage.

McHale may be the one to really watch as she makes her first trip to the third round of a Grand Slam (eighth appearance).

She's had a few big wins this year -- beating world number one Caroline Wozniacki in straight sets in Cincinnati and beating two-time Grand Slam winner Svetlana Kuznetsova twice -- in New Haven and Indian Wells.