I found one really cool set of photos of sisters Venus and Serena Williams practicing before their epic match at the US Open. The photos are chronologically ordered and each one is commented. In this post I'm showing you just some of them.

I find it especially nice that the tennis stars were both accompanied by their partners –  Venus by her fiancé, golfer Hank Kuehne, and Serena by her often-denied boyfriend, rapper Common. Read more »

Serena Williams won the 17th meeting with her sister Venus, an epic match with a final result 7-6 (8-6) 7-6 (9-7), and moved into the semifinals of the US Open where she’ll face Dinara Safina.

Serena, the fourth seed, suffered an early break of serve, but when serving for the set at 5-3 and 40-15 Venus handed the momentum to Serena. Having already seen two set points go begging in the first set, seventh-seeded Venus wasted a further eight in the second set tie-break.

Serena, who now has 9-8 record against Venus (6-5 in Grand Slams) is looking for her 12th Grand Slam final.

In the other semifinal, Jelena Jankovic and Elena Dementieva will face each other. (source: BBC)

Sixth seed Dinara Safina advanced to the US Open semifinals with an easy 6-2 6-3 win over 16th seed Flavia Pennetta.

Safina earned a service break in the second game and later broke serve again to close out the first set. In the second, Pennetta broke at love to go up 2-1, but Safina broke right back, and then again for a 4-2 lead. The Russian cruised the rest of the way.

The 22-year-old Safina will play one of the Williams sisters in the semis.

On day eight of the US Open Safina said: "Sometimes, wherever I am, I feel like I have already been there for a year." Hopefully she has overcome that feeling, she will need to be fully rested to overcome her next opponent.

BTW: I really like this quote of Pennetta:

Can you just talk a little bit about your decision this year to really make a big push and to commit to your tennis?

"What decision? I just work a lot. It's not a big decision." We can all learn from this! (source: The New York Times, photo: safina-dinara.com)

Fifth seed Elena Dementieva eased past 15th seed Patty Schnyder 6-2 6-3 to reach her fourth US Open semifinal.

The Russian broke twice to take the first set. In the second set the Swiss broke back to level at 3-3, but Dementieva broke back again and didn’t lose another game until the end of the match. The gold medalist at the Beijing Olympics Dementieva has now won 11 matches in a row.

In the semifinals Dementieva will play either second seed Jelena Jankovic of Serbia or 29th seed Sybille Bammer of Austria. (source: BBC, photo: Getty Images)

Serena Williams beat Severine Bremond 6-2 6-2 in the fourth round of the US Open and set up a quarterfinal clash with sister Venus. Although happy to advance, the sisters are disappointed that they need to face each other so early into the tournament.

"It sucks," said Serena.

"It sucks that it can't be the final. At least the semis. It's so soon. It's just disappointing to be so soon."

Serena and Venus Williams dominated the US Open for four years – Serena won the title in 1999 and 2002 and her older sister in 2000 and 2001. They are now the only Grand Slam champions left in the draw, plus, they haven’t dropped a set yet in the tournament. (source: Reuters, photo via news.com.au)

Venus Williams reached the quarterfinals of the US Open for the ninth time as she defeated Agnieszka Radwanska in straight sets 6-1 6-3.

The seventh-seeded Williams quickly won the first set, and staved off a mini-fightback by the Polish ninth seed in the second.

There are high chances of an all-Williams quarterfinal. Venus will face sister Serena if Serena beats unseeded Severine Bremond of France. (source: Reuters, photo: Getty Images)

Number 16 seed Flavia Pennetta of Italy eased through to a matchup with Russian sixth seed Dinara Safina with a 6-3 6-0 victory over Amelie Mauresmo in the fourth round of the US Open.

Former world number one Mauresmo was struggling to find form for a long time, but has recently shown signs of getting back on track. In the match against Pennetta, however, Mauresmo produced 14 doubles and 40 unforced errors, and eased the Italian’s way into her first Grand Slam quarterfinals.

Safina and Pennetta have played each other four times, and all the encounters were won by the Russian. (source: Reuters, photo: Getty Images)

Because of exhaustion Dinara Safina had almost given up her fourth-round match up with German qualifier Anna-Lena Groenefeld before it even started but her coach gave her much needed support and the Russian sixth seed advanced 7-5 6-0.

"I finished the warm-up and I just said, I cannot push myself anymore. I could not stop from crying," said world number seven Safina, who has reached six finals in her last seven tournaments.

"(My coach) said, 'We know that you're not a machine. Just go on the court and do whatever you can this day. If it's 20 percent left in your body, just give this 20 percent.

"'Don't use another percent just throwing the balls around and shouting. Whatever you have, just try to concentrate and put it into the game.' So that's what I did today."

World number 141 Anna-Lena Groenefeld, who had defeated both 11th seed Daniela Hantuchova and 17th seed Alize Cornet at the US Open, was a tough opponent in the first set, but collapsed in the second. (source: Reuters, photo: safina-dinara.com)