Sweat trickling down his face, his pulse amped to DSL speed after a StairMaster session, Mark Cuban is short of breath but not at a loss for words.

This is his favorite topic, his baby, his No. 1 acquisition, the high-definition-with-crystal-clear-resolution focal point of his otherwise frenetic universe.

Until recently, that would have described his beloved Dallas Mavericks. But now, sitting in the team's weight room before a recent game, his thoughts drift to his 2-month-old daughter, Alexis.

"I'm not saying I know everything about fatherhood, but I can say that what I do know, I love," Cuban says. "It's the best thing that's ever happened to me by a long shot."

Endorphin rush? Perhaps, except that Cuban's family and friends say he's been positively goo-goo, ga-ga since Alexis' birth.

But more mellow? Less outspoken? Less attentive toward his eldest "baby," the Mavericks?

"Everyone says, 'Your daughter's going to change you,'" Cuban says. "If anything, to me, that's a reflection that you really didn't believe in who you were before. I look at it as the exact opposite."

He shared those comments three weeks ago. True to his word, after a Mavericks overtime loss Nov. 8 in Memphis, Cuban harshly criticized the officiating, citing at least six calls or no-calls that he deemed questionable.

The NBA did not fine Cuban for his comments, and it has been nearly two years since the league last docked him. Some fans and media (wishful thinkers, Cuban calls them) pointed to that as evidence that the billionaire owner was softening.

After all, in a span of 12 months, Cuban:

Married Tiffany Stewart in September 2002.

Turned 45 in August.

Became a father on Sept. 25.

This constitutes a transformation for anyone, even for someone as tenaciously resolute as Cuban.

"Personally, I think being married to Tiffany has been a great thing for Mark, a calming influence in a hectic life," says Todd Wagner, who with Cuban co-founded Broadcast.com, which they sold for $5.7 billion to Yahoo in 1999.

"And I think fatherhood can provide more of the same. But make no mistake, Mark plays the sport of business to win, and that hasn't changed one bit."

Wagner would know. They have been friends since meeting at Indiana University in the early 1980s, and they remain business partners.

Two days before Alexis was born, Wagner and Cuban announced that they had purchased Landmark Theatre Corp., the nation's largest art-house theater chain. That completed an entertainment trifecta to go with Cuban's high-definition television channel (HDNet) and Wagner's film and TV production studio (2929 Entertainment).

"It doesn't matter if you've got five bucks or $500 million; it's got to be the same feeling," another IU friend, Ben Kadish, says of Cuban's entry into fatherhood.

"It's called making him complete. Needless to say, he had everything else in the world, didn't he?"

Alexis Sofia Cuban was a week overdue when she entered the world at 10:38 a.m. at Presbyterian Hospital of Dallas' Margot Perot Center.

Tiffany and Mark arrived at the hospital about 8 p.m. the previous night. Cuban says he was relatively calm, but nearly fainted the morning of the delivery because he had eaten very little.

Tiffany's sister, Jamie Stewart, also was in the delivery room. Her recall of the father-to-be's "calmness" is slightly different.

"He was so anxious, he was compulsively munching on dry cereal to calm his nerves, but the chomping sound was severely irritating his wife," she says, describing an antsy side of Cuban no doubt familiar to Mavericks coach Don Nelson.

Jamie says Cuban was extremely supportive, "very much a coach," and "very much in awe of his new little girl."

In fact, Jamie says that both sets of grandparents, Mark's two brothers and their wives, and Tiffany's two sisters left the hospital that afternoon without getting to hold Alexis.

"I have two words for you: 1. Baby. 2. Hog," Jamie says of Cuban. She adds that it wasn't until Jamie and her sister Julie returned with dinner that evening that they got to hold Alexis -- by using the food as ransom.

Of course, exuding instant unconditional love makes Cuban no different than most parents. But this new father happens to own the Mavericks, was a self-made billionaire by his early 40s and tends to evoke and stoke strong feelings -- positive and negative -- from masses he has never met.

All the more reason, Cuban believes, to be fiercely protective of his family's privacy. For this story, he agreed to pass along e-mailed questions to Tiffany, emphasizing that it would be her choice whether to respond (she didn't). But he also realizes that any significant change in his life is news, which perhaps is why he agreed to provide a photo of himself holding Alexis -- a sneak peek, without intrusiveness, on his terms.

The bottom line is that Cuban simply loves talking about Alexis, particularly The Moment that fathers experience: that sudden, overwhelming wave of emotion and realization.

"It's what it symbolizes," Cuban says. "Everything that my wife went through. Everything you've dreamed about and she's dreamed about. The fact that you were a family before, but now you're a family.

"I've always felt you go through stages in your life with your accomplishments and your disappointments and changes, whether it's high school, college, first job, that kind of stuff. The minute she popped out, you just walked through this new door."

So far, true to his word, Cuban has proved he can juggle fatherhood and remain an involved sports franchise owner.

Nelson and the players say they have seen no difference in the way Cuban approaches games, or personnel and operational decisions.

Oh, there are subtle things. Cuban wears his hospital nursery-unit wristband as a constant reminder of Alexis, kissing it for good luck during games. He also kisses Alexis for good luck at halftime on those nights Tiffany brings her to home games and stays in a noise-proof "bunker suite."

He also engages in some parental boasting. Before a home game earlier this season, as another new father, Mavericks guard Michael Finley, was face-first on a massage table, Cuban teasingly noted that Alexis "doesn't have chipmunk cheeks like Fin's baby girl."

Cuban says that since Alexis' birth he has significantly decreased his travel. He says he probably won't attend every Mavericks road game; he had rarely missed road games since purchasing the team Jan. 4, 2000.

Now, Cuban says, any business he has out of town, he tries to synchronize with Mavs road games.

"Before, I wouldn't ask someone to go out of their way to meet me around a game," he says. "Now I go out of my way to ask them to change their schedule to be flexible to mine."

E-mail and conference calls, he says, also enable him to conduct more business from home. Often, he says, he does so while holding Alexis at his chest, giving Tiffany an opportunity to sleep in. In Cuban's mind, that's the least he can do.

"She's the best mom in the world, up all the time," Cuban says. "I wouldn't have the temperament, the patience, the willpower to do what she's done.

"So I have a newfound respect, not only for her, but for all women."

But if fans and media see this softer side of Cuban and assume that, gradually, he will be less likely to scowl or bark at referees or speak his mind on what he deems important issues, think again.

"If anything, you say them more because you want to be able to say to your kids that, 'If you believe strongly enough and do your work, you can feel confident enough in what you say,'" he says.

"And if you feel confident in what you're saying, you should say what you believe and not let anyone guide you any other way. Your job is not to fall in line. Your job is to be yourself."

Impending fatherhood, after all, didn't prevent Cuban from commenting this summer on the Kobe Bryant sexual assault case.

While calling it a "tragic situation" on both sides, Cuban noted Dallas' season opener against the Lakers in Los Angeles would get huge TV ratings and that, "from a league standpoint, it's good for business."

NBA commissioner David Stern called Cuban's comments "misinformed and unseemly," but Cuban matter-of-factly notes that the Lakers-Mavs TV ratings were, indeed, through the roof. He also was criticized by Lakers owner Jerry Buss for suggesting that the Bryant-Shaquille O'Neal feud may be more divisive than the public realized. He makes no apology for that, either.

So how does Cuban account for his dramatic drop in fines after being docked more than $1 million during his first two seasons?

"I think it's just come full circle more than anything else," he says. "Not only have people gotten used to me, they're starting to listen to me.

"Whereas before it was, 'Be a good little owner. Shut up and don't say anything.' Now it's, 'Why can't teams have an owner like Mark Cuban, or the Maloofs [Sacramento's Joe and Gavin], who are far more visible and involved?"'

Cuban notes that several Mavericks marketing innovations, some of which are technically against league rules, have been copied and embraced league wide.

"At the end of the day, I've got $300 million invested in this thing," he says. "And I'd rather have a better product than a pat on the back."

Perhaps that is the point. Perhaps now, when Cuban looks around, within his home, within and outside his businesses, there are far more developments to like and fewer details he would change.

Friends and family say he had looked forward to fatherhood for a long time. One of Mark's brothers, Jeff, has a 2-year-old son. Tiffany's oldest sister, Julie, has a 21-month-old daughter. Jamie Stewart says she believes the time spent and "practice" Mark and Tiffany had with their niece and nephew influenced their decision to enter parenthood.

"Mark would love to have a son to play hoops with," Stewart says.

College buddy Kadish, who lives in Chicago, married in his late 30s and had his first child two years ago. He goes so far as to predict this about Cuban and fatherhood: "I'm sure it will mellow him."

That remains to be seen. One constant Cuban has exhibited since buying the Mavericks is unpredictability.

"Like everybody says, 'You never know until it happens; it'll change your life,'" Cuban says. "Everybody's right.

"At my age and where we're at as a family, it's great because it makes you feel like you're 18 years old again. It's a whole new part of your life."

Mavericks owner Mark Cuban on the birth of his daughter, Alexis: "It's the best thing that's ever happened to me by a long shot."