Who is this kid challenging Joker?

Alexandr Dolgopolov, he had a lot of success early in the year, along with Canada's Milos Raonic and shot out of nowhere into the Top 30.

He upset Soderling at the Australian Open and had a couple of nice clay-court showings, but hasn't done much since.

this opening set with Djoker and Dolgopolov has easily been the most entertaining of the tournament thus far.

Amazing stuff.

even though Joker won...that was the most entertaining tiebreak of the tournament

come on fish

Wozniacki proving that she's overrated...still hot though

I wouldn't say that she's overrated. She's incredibly consistent- outside of winning slams.

she'll break through at some point. Probably needs to alter her season strategy if she wants to gear it up towards winning slams consistently.

I hope she wins one soon so the only non williams-sister stories in women's tennis can be something other than "how can the #1 ranked player not win slams"

great comeback by Caroline after being down early in the 2nd set.

Now she looks in control to start this 3rd. Still got Roger to come up!

I want Roger to go out there and just beat the crap out of Monaco- no reason he should get caught in a battle tonight.

What a great third set from Caroline against the depleted Kuznetsova. Excellent comeback and win for her tonight!

20 minute first set. I'd say that's coming out and taking it to him.

Whoop! Thank you, Roger! I'll give you 5 blue parachutes/diamonds.

Sharp as a freakin' tack.

so the rain is going to turn whatever day they begin play into an amazing day of tennis.

If it goes tomorrow it'll be awesome. However, looks like it'll wait till thursday cause the rain chances at 90%. Wonder how much they'll be able to get in if anything.

Going to be a crazy finish to this tournament.

Rafa taking a ridiculously long time to come out after they already interviewed Muller.

People on the set are questioning what the hell is happening, and saying tournament needs to get more strict on this stuff.

Rain argh!

Shoutout to Jack Sock- he and Oudin are in the finals for Mixed!!

My man John Isner gets the win against Simon!! Whoop!!

And hey! Andy Roddick beats David Ferrer. Isn't that nice?

No, but seriously. That was a great win for Andy, and he absolutely had the right argument today about not playing on a court that wasn't ready. Great job to come out and just play tennis after the frustration.

Could we get an all-american semi-final on 9/11 at the US Open in New York? You can't write movie scripts like this.

If you're not watching this Djokovic/Tipsarevic match, you should be.

very tense moment in the Fed/Tsonga match.

Fed up 2 sets to 0, up 4-3 and Tsonga fighting off multiple federer break points.

Here's another one.

oh and he double faults. Not the way you want to see that happen.

Fed serving for the match.

BEAUTIFUL tennis from Roger against Tsonga tonight-great win after the recent troubles he's had against the Frenchman. Tsonga never really seemed to be able to completely get into the match; Roger just served too well and controlled the majority of the points. That semi with Novak is shaping up to be another epic showdown.

Some great tennis scheduled for tomorrow: Nadal vs. Roddick and Murray vs. Isner. Keep in mind that this is my man Isner's first appearance in a grand slam QF!

USA! USA! USA!

what a great match from Roger. He looks in top form.

30 consecutive QF's....that has to be one of the greatest streaks in all of sports.

I can't imagine if he brought it to 34.

Djoker/Roger in a SF.

Before that we got americans in both QF's tomorrow!

Awesome stuff.

Dang... Tough match. Great fight from Isner to get the third set and take the 4th to a tiebreak. Andy Murray was just too tough today.

Excited for Rafa/Roddick!

It is hard to believe that Nadal can last much longer the way he plays. His body is going to break down sooner or later.

Nadal played a fantastic match, but that was seriously pathetic.

Zero forehand winners. Zero.

well. 1-4 into the SFs.

Tomorrow should be awesome.

Congrats to Jack Sock and Melanie Oudin for winning the Mixed Doubles!!! Great accomplishment for our two young Americans!

great action in this opening set.

Great first for Federer

His first service game in the second will tell how the rest of the match will go.

Fed is playing confident tennis.

Djoker is getting Fed up...by the crowd...no pun intended