NEW YORK -- Ivan Lendl, navigating the Merritt Parkway through the leafy Connecticut countryside at breakneck speed, laughed loudly into the phone Wednesday morning.
He was once the shining standard of consistent excellence in tennis; from the 1985 U.S. Open to the 1988 Australian Open, Lendl reached 10 consecutive Grand Slam semifinals.
"If you called me eight years ago and said 'There will be a guy who comes along, and he'll be in 21 straight Grand Slam semifinals,'" Lendl said. "Well, I would be looking for a polite way to end the conversation as quickly as possible because I'd be talking to somebody out of their mind."
Then he laughed again.
"It's just ridiculous," Lendl added. "There is no other way to say it. You can't explain it to people, it's just absurd.
"When you slow down and really think about it, it's almost obscene."
Said Federer, "I guess when it snaps is when it's a pity. As long as it's going, you go with it."
Let's try and put this into some sort of context. Beginning with Wimbledon in 2004, Federer has won at least five matches in each of the Grand Slam events through the current U.S. Open. That's 5½ years without a hiccup, 110 consecutive match wins through the quarterfinals of the most dangerous draws in the sport.
"It's pretty safe to say," said ESPN analyst Darren Cahill, "it's one record that will never be broken."
Jose Higueras, the USTA's director of coaching for elite player development, knows Federer well. He worked closely with him last year.
"The consistency of his play is amazing," Higueras said. "I would put it up with any major run in any sport ever. He is hitting so easy and so winning so much, you tend to overlook the streak."
A short list of relevant (and scintillating) sports streaks:
• Joe DiMaggio's 56-game hitting streak in 1941 for the New York Yankees. Pete Rose's 44 games is second on the all-time list.
• Edwin Moses' 107 consecutive victories in 400-meter intermediate hurdles finals. The American went 9 years, 9 months and 9 days without a loss before falling to Danny Harris in 1987.
• Cael Sanderson's 159-0 wrestling career at Iowa State. He remains the only undefeated wrestler in college history, winning three NCAA titles at 184 pounds and one at 197.
• The Edmonton Oilers' Wayne Gretzky's streak of scoring at least a goal or an assist in 51 straight games in 1983-84.
• Orel Hershiser's run of 59 consecutive scoreless innings in 1988 for the Los Angeles Dodgers.
• Russia's Greco-Roman super heavyweight wrestler Alexander Karelin went 13 years without losing a match -- a full decade without surrendering a point -- before losing to Rulon Gardner at the Sydney Olympics.
Certainly, Federer's feat belongs among them. How high should he be on that list? That's a highly subjective judgment.
In tennis, the discussion usually begins with Martina Navratilova's 74-match winning streak in 1984. This one, however, feels different. What does the streak (should it be capitalized?) say about Roger Federer?
"It says," Lendl mused, "how much better he is than anybody else."
Cahill credits the streak to the team Federer has assembled around him: Wife Mirka, coach Severin Luthi, trainer Pierre Paganini, physiotherapist Pavel Kovac and agent Tony Godsick.
"To stay healthy and strong for that long a period of time is amazing," Cahill said. "The intelligent scheduling, playing the right events, peaking for the big tournaments.
"It's also a tribute to Roger's mindset, to his drive."
If Federer reaches the final here, he would become the first man in history to reach all four major finals in the same year on three occasions (2006, 2007, 2009), surpassing Rod Laver's Grand Slams in 1962 and 1969.
"To his credit," Cahill said, "Roger wants to step up in the big moments, on the big stage. He wants to win those matches. He's never shied away from the pressure. He says, 'I want the No. 1 tag, I want the pressure because that's what it's all about.'
"I think he's that special kind of athlete, that special kind of person who says, 'Give it to me, give it to me,' and he steps up to the plate.
Federer, for the record, has a few streaks going at the National Tennis Center. The win over Soderling was his 39th in a row here, and he is bidding to become the first man since Bill Tilden (1920-25) to win six consecutive U.S. Opens. How far is he ahead of the field? Federer has won a record 15 majors; all the other active players, including Nadal, have 13.
When the subject comes up, Federer tends to downplay the significance of his semifinal streak.
"It's not something I aim for," he said earlier in the tournament. "I'm aiming for [something] bigger, to be quite honest. I try to defend the title here, not just to reach another semi so my streak stays alive.
"I've got to look at the bigger picture, that I stay healthy, that I play a proper game, I choose the right shots, break it down. All of a sudden you forget about the streak. "
Greg Garber is a senior writer for ESPN.com.