WIMBLEDON, England -- Even before the question was completed, Bob and Mike Bryan glanced at each other, their brown eyes locking for a second or two. You could almost feel their brains accelerate into hyperspace.
How many hours have the 32-year-old twins from California spent together on the tennis court?
Earlier, their father, Wayne, in an elaborate calculation, had arrived at a staggering figure. For the brothers, sitting in cramped Interview Room No. 3 at Roland Garros, it wasn't merely a question but a task, a competition.
All-time ATP doubles titles
Bob whipped out his iPhone and started crunching numbers. Mike closed his eyes and started talking to himself.
"It's got to be more than 27,000 hours," Mike said, about 10 seconds later.
"I have 30,000," said Bob, a little miffed that Mike had beaten him.
Wayne had given a range of 26,000 to 30,000 hours -- or somewhere between two and three hours a day over the span of their entire lives.
"It's about the time," Mike said, "not necessarily the tennis. That made all the difference in the world."
A month ago in Madrid, the Brothers Bryan won their 61st ATP World Tour doubles title, equaling the all-time record of Todd Woodbridge and Mark Woodforde. The Bryans can break the mark here at Wimbledon, where they won the title in 2006 and reached the final a year ago.
"I'm getting chills that they're about to surpass our record," Woodforde said, laughing, from his California home last month. "Did we think someone so soon afterward would break it? No. We're fully aware that Mike and Bob are getting close. There's no ill feeling."
Tennis is far down the food chain of popular sports in America, running around No. 10, somewhere behind golf and ahead of boxing. Within the context of tennis, doubles -- even though it was recently retooled to make it more fan-friendly -- is virtually lost in the glare of singles. The Bryans' quest to break the record is a rare 15 minutes of fame for their quaint niche in the sport. They have been profiled in a "60 Minutes" feature and a generous Sports Illustrated spread.
"In the doubles world, they are like Rafa [Nadal] and Roger [Federer]," said their coach, David Macpherson. "It's not easy being No. 1, with expectations for yourself and everybody else. It's exhausting, because doubles is so hard to dominate. It's good to see them getting their due."
They share everything, including a rock-and-roll band, prize money and, with their girlfriends, houses in California and Florida. They are uber-hyperactive on the court, sometimes vibrating at unnatural frequencies in moments of duress (in terms of racket tension, they are somewhere past 90). But when they step outside the lines, they are "very chill," as Macpherson says.
As it turns out, they are very different people. Mike, who was delivered two minutes earlier by mother Kathy, comes across as the older, more responsible brother.
"It surprises people they're so different -- because they look the same," Macpherson said. "Bob rolls out of bed and hits 130 mph serves. His body seems to work great without much effort. Mike is very heath-conscious, very regimented, [follows] a gluten-free diet. He spends a lot of time crunching and is very disciplined.
"They're not clones, that's for sure."
Until recently it was easy to tell them apart. Bob usually favored a beaded necklace and Mike had a mole on his neck. When Mike had the mole removed, the only noticeable difference became their size: Bob, at 6-foot-4 and 202 pounds, is an inch taller and 10-12 pounds heavier. If you look hard enough, you can see it in their faces. On the phone, no one -- not even their parents -- can distinguish them.
They weren't such strapping lads when they played their first Grand Slam event 15 years ago. They were gangly, wide-eyed 17-year-olds at the National Tennis Center in New York.
"They were on the smaller side in stature," Woodforde said. "We were talking with Grant Connell and Patrick Galbraith, and they were going to go play these kids who got a wild card. They pointed to these two little guys, who looked like they were walking to their execution, just caught in the headlights.
"To see them grow from that, to an even grander stage now … it's really amazing. I see similarities between the way they play to Todd and I. I see a progression of the sport."
The Woodies were at Roland Garros to play in the Legends tournament. When they first came upon the Bryans, eating lunch in the players' lounge, Woodbridge ran over and playfully kicked Mike in the knee.
"We idolized the Woodies," Mike said. "It's crazy how fast it came. A few years ago we didn't think it would ever happen."
It's about the reps
The origin of their sometimes-disturbing intensity is not hard to locate.
Recently, a reporter dropped a casual e-mail to Wayne, the Bryans' father, and within 24 hours the inbox was jammed with 29 replies. There were stories about the boys, personal observations and all kinds of stats.
"I'm just trying to make your job easier," Wayne said.
All-time doubles titles by brothers
Some days later, he checked in when he was somewhere between Camarillo, Calif., and Malibu. When they play, the Bryans appear to have telepathic command of the points, two bodies and a single mind. They talk less than most doubles teams. Much has been written and said about their twin-ergy -- several doubles opponents have called it an "unfair" advantage -- but Wayne rejected the theory that common DNA has resulted in uncommon results.
"Here's the truth," Wayne said. "All the writers, players and fans -- they all think they have this ESP thing, this unbelievable twins chemistry. We've always let them believe that. But I don't believe in hocus pocus, aliens or conspiracy theories.
"This isn't about that, it's about reps. Their mother played [tennis] on their due date. They played thousands and thousands of matches together, in juniors, college and the pros. They've played together more than any team ever did, more than any team ever could.
"Bob hits a big serve down the 'T' and Mike goes to cross and poaches. He bangs the volley and Bob comes in, sees Mike's gone across, and he's covering. All they're doing is reacting to stimuli. It looks like they knew how they were going to play it before it happened because they've seen that play 8,000 times."
Their parents' secret? Growing up, all those hours never felt like work.
"That's the cornerstone," Wayne said. "You've got to make it fun, whether it's marine biology or dance or tennis. I'm convinced people don't want to work hard, they want to have fun. It doesn't have to be drudgery to follow your passion.
"What we do in America and Europe is we lead with technique and theory. Most kids quit playing piano before they ever play a song. They want to play pop tunes. I say teach them their favorite radio song first, then later teach them the hard stuff."
Wayne was the professional at a local tennis club in Southern California, and Kathy -- who as a player reached the quarterfinals of mixed doubles at Wimbledon in 1965 -- also taught there.
The twins attended their first Davis Cup match at the age of 10 when the United States hosted Mexico at La Costa. They met Rick Leach and his partner, Jim Pugh, on their way into the stadium. In a brief conversation, the just-crowned Long Beach Boys 10 doubles champions learned that Leach had once held that title, too. The Bryans then rooted hard, waving American flags for Leach and Pugh, who won their match in four sets. And so, the hook was set.
They played youth and junior tennis; when they both reached the final (on more than 30 occasions), one of them would default. They earned scholarships to Stanford University, playing for two years and winning two national team titles. They turned pro in 1998.
Before their first Davis Cup match, in 2003, captain Patrick McEnroe wished them luck.
"And they just looked at me with this confidence," McEnroe said. "They said, 'We've been waiting 25 years for this moment.' They say stuff like that all the time."
In 2007, they helped the United States to the Davis Cup title. They are the winningest doubles team in Davis Cup history.
"Am I surprised?" Wayne asked. "No. That's what their goal was when they were 8, 9 and 10. To be truthful, I'd be more surprised if they hadn't accomplished those things."
Greg Garber is a senior writer for ESPN.com.