NEW YORK -- Andy Roddick's tennis game has its ebbs and flows, but his postmatch news conferences are consistently excellent. His sharp, biting sarcasm is always in top form.
On Tuesday night, after he advanced to the quarterfinals here at the U.S. Open, Roddick was asked about the physical condition of his opponent, Novak Djokovic. A reporter was explaining that the Serbian player had complained of an injured right ankle when Roddick cut him off, sparking this charming exchange:
Roddick: Isn't it both of them? And a back and a hip?
Reporter: And when he said there are too many to count
Roddick: And a cramp.
Reporter: Do you get a sense right now that he is
Roddick: Bird flu.
Reporter: A lot of things. Beijing hangover.
Reporter: He's got a pretty long list of illness.
Roddick: Anthrax. SARS. Common cough and cold.
And although severe acute respiratory syndrome might be a little over the top -- to say nothing of anthrax -- Roddick's point was that Djokovic tends to the dramatic with respect to his physical ailments.
"If it's there, it's there," Roddick said. "There's just a lot. You know, he's either quick to call the trainer or he's the most courageous guy of all time. I think it's up for you guys to decide."
If this were football, it would be incendiary fodder for the locker room bulletin board. And so, the battle lines for Thursday's tasty meeting between No. 3-seeded Djokovic and No. 8 Roddick are drawn -- in the sand. How will beleaguered Djokovic -- he is, in fact, nursing ankle and hip injuries -- fare against Roddick, who, along with Rafael Nadal, played only one set over the minimum through four matches?
There could be no longer shot than the No. 130-ranked player from Luxembourg, a tiny country wedged between France, Germany and Belgium that has fewer than a half million citizens. Muller is the lowest-ranked player to become a U.S. Open quarterfinalist since Nicolas Escude crashed the party in 1999. He was understandably breathless after bouncing No. 5 seed Nikolay Davydenko in a spectacular 12-10 fourth-set tiebreaker.
"I think it was the most amazing tiebreaker I've ever played in my whole life," Muller said. "It's true I have nothing to lose, but on the other hand I have a lot to win. The way I am on the court right now, I would love to stay like this through the rest of my career."
Muller came in with a 3-4 record in ATP-level matches and has spent the bulk of his season playing minor events in places such as Wroclaw, Poland; Humacao, Puerto Rico; and Izmir, Turkey. It was hardly surprising when he lost the first set of his opening qualifying match here in an 11-9 tiebreaker to Algerian Lamine Ouahab. Muller rallied to win in three sets, then handled Adrian Mannarino and Tobias Kamke -- winning the pivotal third set 6-2 -- to advance to the main draw.
Muller has been essentially unconscious for four main-draw matches now, and he has played a total of seven matches here, comprising 26 sets. Coming in, Muller had never come back from a 2-0 deficit in sets. He did it twice in a row, erasing well-regarded Tommy Haas and Nicolas Almagro, to reach the fourth round opposite Davydenko.
History might have given the Russian pause, for Muller has routinely (and inexplicably) played above his head against terrific players. Roddick knows this better than anyone. It was Muller who took down then-No. 3-ranked Roddick in the first round here in 2005, following up on his earlier upset of Nadal -- also ranked No. 3 when he lost -- in the second round at Wimbledon.
"He didn't beat Andy for nothing here a few years ago," Federer noted. "That's why I definitely won't underestimate him: because he's a good player.
"He's on an unbelievable roll. He maybe never should have been in the quarters because he could have been knocked out in straight sets by Tommy. I hear he couldn't win matches anymore in Challengers, and now he's in the quarters in the U.S. Open. He's playing the greatest matches here of his life."
USA Network analyst Jim Courier remains convinced that Federer is not operating at anything close to 100 percent.
"Let's all step back, take a deep breath and admit that Federer is still sick," he said Wednesday. "It's pretty clear to me he's still not right."
How does Courier know this?
"Watch him move," Courier said immediately. "Watch a tape from last year. You don't lose a step at 27 years old -- but he's lost a good half-step.
"If I were him, I wouldn't talk about it, either."
Roddick, whose form has been spotty for the past several months thanks to a variety of injuries, has looked good, too. He elected to pass on the Olympics, and now, as those who played in Beijing have struggled here, it looks like a good decision.
"I don't know if it was the right one or not," Roddick said. I'm certainly not going to give the credit for me playing well here to not going to the Olympics because I played like crap while the Olympics was going on."
Part of Roddick's resurgence must be credited to a filling-the-void coaching stint on the part of Patrick McEnroe, the U.S. Davis Cup captain. Including last year's four-tie run to the title and this year's two victories to advance to the quarterfinals in Spain -- plus Roddick's four wins here -- McEnroe has a 10-0 streak going.
"No different than we've done at Davis Cup for the past however long," Roddick said, downplaying McEnroe's influence. "Just going over matches -- I don't know if you can put a whole lot to that. It's been great. It was the obvious best choice for kind of a short-term solution here.
"I think we were both comfortable with that."
Contrast that with Djokovic, who, after his stirring five-set victory over Tommy Robredo, said in an on-court interview, "I need to stand next to the net, otherwise I will fall down."
If Djokovic is as uncomfortable with all his injuries as he says, Roddick might be looking at a semifinal match that would feature the winners of the past five U.S Open crowns.
"I'm in line to make something really good happen," Roddick said. "If you get through the next one, then you got a shot at it."
Greg Garber is a senior writer for ESPN.com.