Andy Roddick cools off during Tuesday's five-set defeat.

AP

What Happened?

Another temperate day in Melbourne saw a major upset, another minor one, and two major scares of the tourney's top seeds.

• Sixth-seeded Venus Williams squandered a one-set lead in a shock loss to No. 16-seeded Li Na. It was a mistake-ridden match that saw the players combine for 110 unforced errors and 17 breaks of serve before Li escaped with the 2-5, 7-6 (4), 7-5 victory.

• Defending champion Serena Williams survived a major scare in the other women's semifinal, rallying from a 4-6, 0-4 hole to defeat Victoria Azarenka.

• Top-seeded Roger Federer overcame a listless first set to claim a four-set victory over Nikolay Davydenko in the first men's semi.

• France's Jo-Wilfried Tsonga earned a five-set victory over Novak Djokovic, who battled stomach issues throughout the latter half of the match. (Djokovic doesn't know what caused it, but remained somewhat upbeat.)

• Match of the Day: Tsonga had never played a five-setter in 37 previous Grand Slam matches before Tuesday. After yesterday's quarterfinal thriller opposite Djokovic, he's played two in three days.

Oz Clicks

Tsonga discussed Djokovic's stomach ailment in the post-match press conference ... The Wall Street Journal goes inside the numbers of Justine Henin's run to the semis ... Andy Murray kept his poker face after Wednesday's victory over Rafael Nadal ... The Christian Science Monitor on why Chinese women are breaking into the tennis elite ... Azarenka reflects on Thursday's gutting come-from-ahead loss to Serena.

Photo of the Day

Venus Williams reaches to return a shot from Li Na of China during Thursday's women's quarterfinal at Rod Laver Arena.

Vivek Prakash/AFP/Getty Images

Go Figure

23 ... Number of consecutive Grand Slams semifinal appearances made by Federer, an all-time record.

10 ... Projected ranking of Li Na after Wednesday's upset, making her the first Chinese player in history to crack the WTA Top 10.

6 ... Number to players to defeat both Williams sisters at the same event. Li can become the seventh on Thursday in Melbourne.

3 ... Number of wild cards to reach a Grand Slam semifinal: Zheng Jie (2008 Wimbledon), Kim Clijsters (2009 U.S. Open) and Henin (2010 Australian Open).

Tweet of the Day

"In tennis, doesn't matter how many titles and money you have, you can still get tight and have a mental melt down."
--Alina Jidkova, former Top 50 player on the comeback trail, after Venus Williams' surprise loss to Li Na, Wednesday, 10:27 p.m. ET

Must-See Video

Highlights from Federer's come-from-behind victory over Davydenko.

What's Happening Today

The Tennis Channel's live coverage begins at 7 p.m. ET (with a men's doubles semifinal). ESPN2 takes over at 9:30 p.m. through 6 a.m. on Thursday morning.

Top-seeded Serena Williams faces No. 16 Na Li in the first women's semifinal around 9:30 p.m. ET. Thirty minutes after the first match, Justine Henin meets Jie Zheng to determine the other side of Saturday's women's singles final.

Later, No. 14 Marin Cilic faces No. 5 Andy Murray in the first men's semifinal (3:30 a.m. ET).

The compete order of play for Day 11 can be found here.

They Said It

"So exciting. Maybe I take the beer tonight."
--Li Na, on becoming the first Chinese player to make the WTA Top 10 with Thursday's quarterfinal win over Venus Williams

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