Rousey swiftly disposes of another opponent before calling out next

Ronda Rousey did what she always does. In fact, she did three things she always does: The Strikeforce bantamweight champion won a fight, she won it in the first round and she won it by armbar.

By submitting former champ Sarah Kaufman in just 54 seconds on Saturday night in San Diego, "Rowdy" Ronda remained unbeaten and looked unbeatable. She disarmed Kaufman with the same swiftness she's shown against most everyone she's gotten her hands on. This was the fifth time in a six-bout professional mixed martial arts career that Rousey has finished an opponent in the first minute.

The only foe with staying power has been Miesha Tate, who back in March lasted until late in the first round and even escaped Rousey's initial armbar attempt. But eventually the then-champ had both her elbow and title belt dislocated by Ronda. Tate fought on Saturday night, too, and after an exciting win over Julie Kedzie -- via armbar! -- would seem to have her sights set on a Ronda rematch.

But Rousey didn't have Tate on her mind in the aftermath of her short night's work. She didn't really have Kaufman on her mind, either, other than to toss out a respectful "You're an amazing athlete" during her postfight interview in the cage. But before that, Ronda wasted no time in rousing the crowd with a few not-so-soft-spoken words for another woman in the fight game.

"First of all, I need to send a challenge to 'Miss Cy-Roid' out there," Rousey yelled, referencing Cris "Cyborg" Santos, the fearsome Brazilian strongwoman who had her featherweight title stripped after she tested positive for the anabolic steroid stanozolol following a December bout. Santos is suspended for a year, but that hasn't stopped her from verbally sparring with Rousey, who got a rise out of the crowd by goading "Cyborg" with "People want to see you have the first fair fight of your life."

The sticking point is that Rousey fights at 135 pounds, Santos at 145. Neither has expressed a willingness to budge, and Ronda was emphatic Saturday night in making her case: "I'm the champ now. The champ doesn't go to you; you go to the champ. Come down to 135, and let's settle this."

Santos was in the arena for the fights. She posted several photos of the cage to Twitter. But who knows if she stuck around long enough to hear the postfight interview? After watching Rousey take Kaufman to the mat just 12 seconds into the fight and lock on the deadly armbar just six seconds later, "Cyborg" might very well have headed for the parking lot ... and then to the nearest In-and-Out drive-through for a couple of cheeseburgers and a shake. Gotta pack on a few extra pounds in order to steer clear of that scary 135-pound champ.

Nah, a collision course is inevitable. Even though Rousey has competed in MMA for just a year and a half after winning judo bronze at the 2008 Olympics, she's taken down every legitimate threat in her weight class. And as she so indelicately put it, Santos has something to prove now that her dominance is shrouded in the doubt of a steroid haze. They must fight. They will fight. Soon. Considering the crush UFC president Dana White has on Ms. Rousey, the showdown might very well end up being the first women's fight in the sport's alpha promotion.

And make no mistake: "Cyborg" Santos might have had the reputation as the most rugged brawler in MMA before she got popped for 'roids, but these days Ronda Rousey is the most dominant fighter in MMA. Not women's MMA but MMA, period. Even pound-for-pound royalty like Anderson Silva, Jon Jones and Georges St-Pierre bow down to the fighter who has only once needed more than 54 seconds to make an opponent quit. And she's done it every time with the same submission technique, a maneuver every opponent knows is coming but no one can stop. If she's a one-trick pony, that's one hell of a trick.

How'd Ronda get to be so tough? After she was done haranguing "Cyborg," she spoke glowingly of her mom. What helped make Rousey the first American woman to win an Olympic medal in judo was her upbringing by Ann Maria DeMars, who happens to be the first U.S. woman to win a world judo championship.

"If your mom woke you up in the morning, jumping on top of you, like, 'Always be ready! Armbar now!' that's kind of like how it gets ingrained in your brain," said Rousey, a smile softening her affect. "You think, 'Oh, my parents are so mean.' And they say, 'One day you'll be grateful.' And you're like, 'No way that'll happen.' Well, she's right. I'm grateful."

Questions? Comments? To reach Jeff Wagenheim or contribute to the SI.com MMA mailbag, click on the E-mail link at the top of the page.