We live-blogged Monday's action from Wimbledon. (Broadcast on ESPN2 and, in some time zones, NBC.) Venus and Serena Williams were defeated today, the first time the two sisters have both lost at Wimbledon on the same day.  4:08: So, with Nadal's victory that means the defending champion's quarterfinal opponent will be the last American left in the singles, Mardy Fish. That wraps up today's live blog. The men get tomorrow off, but there will be four quarterfinal matches for the women.  4:06: Nadal ends it forcefully, with a 40-0 game for a 7-6, 3-6, 7-6, 6-4 victory that took 3 hours and 52 minutes.  4:03: Del Potro holds with a 40-15 game of his own, but now must break Nadal's serve to stay alive.  4:00: Nadal holds in a 40-15 game to get to 5-3 in the fourth set. If He breaks here or holds his next serve the defending champion will be onto the quarterfinals.  3:52: Nadal gets down 0-30 but battles back and holds serve for a 4-2 lead in the fourth.  3:47: Nadal breaks Del Potro's serve for the first time in the match, and takes a 3-2 lead in the fourth set.  3:46: The women's quarterfinals will have eight women from eight different nations (but no Americans). The men's quarters will be nearly as diverse. The matches that are set are: Britain's Andy Murray vs. Spain's Feliciano Lopez; Switzerland's Roger Federer vs. France's Jo-Wilfried Tsonga; Serbia's Novak Djokovic against the teen qualifier from Australia, Bernard Tomic. Mardy Fish will represent the U.S. in the quarters, facing either Nadal or Del Potro.  3:41: Nadal-Potro is the only singles match left to complete today. They're on serve at 2-2 in the fourth set. It's almost 9 p.m. in London.  3:34: Federer is into the quarterfinals, breaking Youzhny to win the fourth set and the match, 6-7, 6-3, 6-3, 6-3. Federer will facee France's big server, Jo-Wilfried Tsonga, in the quarters. Federer is 4-1 against Tsonga lifetime. Youzhny held off two match points in the final game, but killed himself with a double fault that gave Federer another match-point opportunity.  3:24: Del Potro nets a forehand to give Nadal a 6-3 lead in the tie-breaker. Del Potro fights off one set point, but can't hold off the next one. Nadal is up a set as the match heads into the fourth set.  3:20: Nadal leads 4-2 in the tie-break. Del Potro just wasted an easy point, smashing long into an open court.  3:16: Nadal and Del Potro are in a third-set tie-breaker. Nadal gets a quick mini-break for a 2-1 lead.  3:13: The French will have a man and a woman in the quarterfinals. Besides Marion Bartoli moving on by defeating Serena Williams, Jo-Wilfriend Tsonga just won a third-set tie-breaker 7-1 to defeat Spain's David Ferrer in straight sets, 6-3, 6-4, 7-6.  3:06: Del Potro closes out a 40-0 game with an ace, so he and Nadal are 5-5 in the third set and likely headed for a tie-breaker.  2:53: Del Potro holds serve, so his hip can't be too bad. Nadal is still limping occasionally on that sore left foot . . . Federer is up a break quickly in his fourth set against Youzhny.  2:50: Del Potro is back on the court and play resumes. He's moving okay, and he and Nadal are on serve in the third, tied at a set apiece.  2:47: Federer closes out the third set and needs one more set to run his career record against Youzhny to 11-0. He took offense at a lengthy grunt from Youzhny and made a point of uttering a grunt of his own while winning a point.  2:42: And now Del Potro leaves Centre Court with the trainer, so there will be a lengthy delay in Nadal's match.  2:41: Del Potro takes a fall and grabs for his left hip. The trainer is out, and there's a medical break in the third set with the match tied at a set apiece. It's 2-2 in the third.  2:35: Federer is cruising now, up 5-2 in the third set.  2:19: Del Potro closes out the second set with a 40-15 game. The 6-6 Argentinian is going to the serve-and-volley more, and scoring with it. If Del Potro had held onto that 3-0 lead he had in the first-set tie-breaker the defending champion would be in big trouble right now.  2:15: Del Potro gets a second-set break and is serving for the set against Nadal. Federer goes up a break in the third set as Youzhny gives away the game on a double fault.  2:07: Mardy Fish is into the quarterfinals for the first time in his career. He closes out berdych with an overhead smash. Fish drilled 23 aces while winning in straight sets. He'll get the winner of Nadal-Del Potro in the next round.  2:02: Mardy Fish is serving for the match against Berdych. Fish just had a match point, but couldn't deliver against Berdych's serve in a game that went to deuce three times.  1:59: Federer takes the second set 6-3 and evens the match with Youzhny at a set apiece.  1:56: Federer is rebounding from losing his first-set tie-breaker. He's up a break on Youzhny and leads the second 5-3.  1:47: Nadal and Del Potro are on serve in the second set and Nadal doesn't seem to be suffering the way he was at the end of the first set. He just jumped on a drop shot with a sprint, then leaped and spun to put away an overhead, backhand volley.  1:42: Including the medical break for Nadal, his first set against Del Potro took 1 hour and 20 minutes.  1:39: Mardy Fish gets a quick break in his third set and is up 2-1 after taking the first two sets against Tomas Berdych of the Czech Republic. He's the last American hope left in singles, male or female.  1:36: Nadal left the court briefly but is back. Del Potro is clearly upset, and slammed his racket during the break, after losing the tie-breaker. At issue, perhaps, is that Nadal was given a medical break when the first set reached 6-6. Del Potro may be arguing that Nadal's break should have come after the tie-breaker was completed.  1:34: Del Potro double faults on set point to give Nadal the tie-breaker, 8-6. But the key going forward is how Nadal copes with his aching left foot. The trainer has been out one time.  1:30: Del Potro gets to set point, but nets the serve from Nadal. They're at 6-6.  1:27: Mardy Fish keeps the hopes alive for seeing an American in the quarterfinals. He takes the first two sets against Tomas Berdych, winning the second at 6-4.  1:26: Federer loses his first-set tie-breaker to Youzhny, 7-5. Nadal has bounced back in his, coming from three down to tie it at 3-3.  1:23: Nadal is clearly in some pain, but he just survived a lengthy rally and moved well throughout. He trails in the tie-breaker, 3-1.  1:20: Federer is off to a 4-2 lead in his first-set tie-breaker against Youzhny . . . Nadal is back on his feet and beginning his tie-breaker against Del Potro . . . And Mardy Fish is serving to take a 2-0 lead in sets against Tomas Berdych.  1:17: Nadal isn't the only men's contender in trouble. Roger Federer is in a first-set tie-breaker with Mikhail Youzhny of Russia.  1:11: Rafael Nadal has a foot problem. He called for the trainer with his first-set tie-breaker about to begin. He had set point against Del Potro's serve, but couldn't convert. It's 6-6, and he's getting a foot rub. TV is picking up some of the conversating and it sounds like he's having trouble pushing off on the foot. It's his left foot.  12:53: Rafael Nadal is on serve in the first set against Argentinian giant Juan Martin Del Potro, but is uncomfortable with his footing on Centre Court. He just switched pairs of Nikes.  12:37: Fish puts away the first set with a rocket serve that Berdych swats into the net. He wins the tie-breaker 7-5.  12:35: Fish gets the tie-breaker to 6-3, but can't convert the first two set-point opportnities against Berdych's serve.  12:30: Mardy Fish, the only American still alive in men's or women's singles, is in a first-set tie-breaker with Tomas Berdych, of the Czech Republic.  12:14: Novak Djokovic is through to the quarterfinals, beating France's Michael Llorda in straight sets. His next opponent will be the 18-year-old qualifier from Australia, Bernard Tomic.  12:04: With all the carnage in the women's bracket today, here's how the quarterfinals will match up: Maria Sharapova (No. 5 seed) vs. Dominika Cibulkova (No. 24) of Slovakia; Sabine Lisicki of Germany vs. Marion Bartolia (No. 9) of France, who ousted Serena Williams. In the bottom half of the women's draw: Tamira Paszek of Austria vs. Victoria Azarenka (No. 4) of Belarus; and Czech Petra Kvitova vs. Bulgarian's Tsvetana Pironkova (No. 32), who just ousted Venus Williams.  11:51: Pironkova completes the execution. She gets to 40-0, and then closes it out on the second match point with a perfect backhand deep into the corner. This is the first time both Williams sisters have lost on the same day at Wimbledon.  11:47: Venus holds serve and now Pironkova will serve for the match, up 5-3 in the second set.  11:43: Pironkova is a game away from ousting Venus Williams at Wimbledon for a second straight year after holding serve for a 5-2 lead in the second. Venus had a triple break point at 15-40 and couldn't convert. The game went to deuce four times and Venus had one other break opportunity she couldn't cash. Pironkova is killing her with backhand winners down the line.  11:34: Venus gives it right back. An unforced error takes her to deuce, and then she goes long with two smashes. Pironkova gets the break and leads 4-2 in the second set after winning the first.  11:32: Very tough day for the top-rated women. With Serena Williams already ousted, No. 1 seed Caroline Wozniacki also heads to the sideline, losing to Dominika Cibulkova of Slovakia. Wozniacki breezed through the first set, 6-1, but then was beaten 7-6 and 7-5.  11:27: Venus seizes her first break-point opportunity and wins a long rally as Pironkova nets a forehand. The game goes to deuce three times, and Venus fought off three break points. Pironkova still leads the second set, 3-2, with Venus about to serve.  11:19: Pironkova gets a break and goes up 3-1 on Venus in the second set. If Venus goes out this will be the first Wimbledon where neither Williams sister was in the final since 2006. That year, Amelie Mauresmo defeated Justine Henin in the final.  11:14: Pironkova wins a challenge and sails through a 40-0 game. She leads Venus 2-1 in the second set, and has lost only four points on her serve so far.  11:09: Feliciano Lopez, the Spaniard who knocked out Andy Roddick last week, is having a surprisingly tough time against Poland's Lukasz Kubot. Down two sets, Lopez survived a third-set tie-breaker, 9-7, to force a fourth set.  11:05: With Venus serving, Pironkova gets to triple set point. Venus fights off one, but then nets a forehand. First set goes to the Bulgarian, 6-2.  11:02: And now the other Williams sister is in trouble. Venus trails Tsvetana Pironkova in the first set, 5-2. Pironkova has won two of her three matches against Venus. She was a semifinalist at Wimbledon last year.  10:54: Top-seeded Caroline Wozniacki has been pushed into a third set by 24th-seeded Dominika Cibulkova of Slovakia. Cimbulkova won the second-set tie-breaker, 7-5.  10:18: Bartoli addressed the fact she told her parents to go away over the weekend, while she was dealing with stomach problems. "I expressed my anger that way. I'm not proud of it. I'm happy to have both my parents back now." Her mother and father (who's a doctor) were in the friends' box today throughout the match.  10:14: Bartoli, to ESPN: "Beating Serena, it's like a dream come true . . . Against, Serena, she's very imposing obviously . . . I was trying to stay focused on my own game, and forget who I was playing."  10:12: Serena nets a backhand on serve to fall behind 7-6. Bartoli has another match point, and is serving, and rockets a great serve to the outside that Serena nets. Bartoli wins the tie-breaker 8-6 and takes the match 6-3, 7-6. Serena gives a gracious handshake and smile.  10:10: Serena fights off that fourth match point with an ace. 6-6 in the tie-break.  10:08: Bartoli hits her 10th ace to get to 5-5, and then wins a long rally to get to 6-5 and match point, for the fourth time.  10:07: Serena goes up 5-4 in the tie-break, winning a 25-shot rally with a great backhand passing shot, and then launching an excellent serve that Bartoli nets.  10:05: Bartoli goes up 4-3 in the tie-breaker with her ninth ace. Serena has seven.  10:02: Bartoli goes long with a backhand on serve and gives Serena the mini-break in the tie-breaker. Williams up 2-1. But Serena gives it back when she dumps a drop shot into the net. 2-2.  10:00: Serena battles back to break Bartoli and force the second-set tie-breaker. Bartoli double-faulted to set up break point, and then Serena jumped all over a second serve to take the game.  9:56: Bartoli gets to match point again but Serena hangs in on an endless rally and puts it away with an overhead smash. Back to deuce.  9:54: Bartoli gets to double match point with an ace, but Serena battles back to deuce. Match is on the line here.  9:50: Bartoli breaks Serena's serve and now will serve for the match. The French woman was creeping in on Serena's serve, playing in front of the baseline. The break point came on a long rally where Bartoli made a couple of good saves, and Serena eventually went long with a backhand volley.  9:44: Bartoli starts out with a double fault, then closes out at 40-15 game with an ace. Serena erratic with her backhands. 5-5 in the second set.  9:39: Williams up 5-4 but she'll have to break Bartoli to win the second set. She has not fared well when her opponent has been serving.  9:36: Bartoli and Williams continue to battle. It is 4-4 with each holding serve in the second set.  9:30: Williams holds serve to go up 4-3.  9:26: Bartoli and Williams now at 3-3. This has been a strange Wimbledown for Williams. If she is to advance she'll have to play her third three-setter in four matches.  9:21: A wonderful drop shot allows Williams to go up 3-2 in the second set. It remains to be seen whether this is a change of pace for Williams and moves Bartoli off the baseline or whether she just saw a momentary opening.  9:15: Bartoli battles back and it is now 2-2 in the second set. Williams threatened to go up 3-1 but Bartoli controlled her serve and then hit a couple of winners.  9:12: Williams and Bartoli are tied 1-1 in second set. Billie Jean King and Prince William seemed to be having an animated conversation in the Royal Box. Probably about how you have a year to send a gift or why she hasn't seen him at a Team Tennis event.  9:09: Williams is now up 1-0 in the second set.  9:00: Now a sixth set point for Bartoli after a strong serve. And then an ace wins the set 6-3.  8:57: Now a fifth set point for Bartoli but an unforced error puts it back to deuce.  8:55: Bartoli has another set point, her fourth. And for the fourth time, Williams battles back.  8:50: Williams saves the game and possibly the match. She is down 3-5 with Bartoli serving but Williams faced three set points and battled back from all of them.  8:49: Bartoli has had set point three times but Williams continues to battle back. This time an ace gets her back to deuce.  8:45: Williams battles back from set points twice but is back to deuce.  8:44: Bartoli at set point.  8:39: Bartoli is having little trouble with Williams. She is now up 5-2 and did not give up a point in the last game. Williams, who has never lost a set to Bartoli, is serving.  8:36: Bartoli has broken Serena Williams and now leads 4-2 in the first set. Bartoli's aggressiveness in the rallies and second serve is working for her.  8:34: Sharapova at triple-match point. Sharapova has won her match, 6-4, 6-2.  8:31: Peng holds out a little longer. She is now down 2-5 to Sharapova in the second set. Sharapova will be serving for the match. Bartoli is up 3-2 on Serena Williams.  8:27: Williams evens first set at 2-2 as her serve appears to get getting stronger. Sharapova about to close out her match as she's at 5-1 in the second set.  8:23: Williams-Bartoli match remains on serve with Bartoli up 2-1. Sharapova up 4-1 in the second set.  8:21: It appears Sharapova will roll on. She is up 4-0 in second set.  8:19: Serena Williams appeared a bit shaky in the first game but won her service game easily. The Williams power play came into account as she had Bartoli on her heels the entire game. Now 1-1.  8:16: A strong start for Bartoli who aces at 40-15 to win the first game against Serena Williams. Sharapova is now up 3-0 against Peng.  8:12: Serena Williams match with Marion Bartoli is nowabout to get underway. It was Bartoli who flushed her parents out of the stands in her last match. She said it was out of frustration and she did that instead of breaking her racquet.  8:08: The Sharapova train is now at full speed. She is up 1-0 in the second set after winning final three games of the first.  8:04: Fan alert. The British newlyweds Williams and Kate have arrived in the Royal Box and got a nice ovation.  8:00: Sharapova at triple set point. She doesn't need the second two as she aces her way to victory, 6-4.  7:56: News alert! Someone is finally broken in the first set as Sharapova goes up 5-4 and is serving for the first set.  7:52: It is now 4-4 in the Sharapova-Peng match with all eight games won by the server. Serena Williams is about 10 minutes away from her match with Marion Bartoli.  7:45: Peng seemed to give Sharapova an opening to break her but then served an ace followed by an unreturnable serve. She now leads 4-3 in the first set.  7:42: Now 3-3 with Sharapova and Peng each holding serve. Only Peng on Sharapova's first service came close to breaking either player.  7:38: No breaks yet as Peng is now up 3-2 in the first set.  7:34: Sharapova, the 4-1 pre-tournament favorite, has made it 2-2 by blitzing Shuai Peng on her service. That is the best she has looked in the four games. One weather note: Pam Shriver reports that temperatures are now in the 90s. Something worth watching.  7:31: Shuai Peng has taken a 2-1 lead against Sharapova. She has won both her service games and early on has looked more comfortable than Sharapova who struggled on some points during her service.  7:30: Maria Sharapova and Shuai Peng are 1-1 in the first set with each holding serve.  See photos of: Serena Williams, Maria Sharapova, Venus Williams, Andy Murray, Mardy Fish
Wimbledon blog: Serena and Venus out; Nadal, Federer and Fish advance - Game On!: Covering the Latest Sports News