Lesnar just keeps getting better

Brock Lesnar had never gotten punched in the face like he did when Shane Carwin unloaded on him.

Lesnar had barely taken any direct shots in his brief, championship-winning, mixed martial arts career. And Carwin had arguably the heaviest hands in the game anyway. So this was the moment everyone had been waiting for.

Could Brock take a punch?

The ultimate answer was yes. Lesnar wound up taking a barrage of Carwin strikes, survived Round 1 and eventually retained his Ultimate Fighting Championship heavyweight title last July. He defends that belt Saturday in Anaheim, Calif. at UFC 121 against Cain Velasquez.

Initially, though, Lesnar didn't handle Carwin's blasts very well. He backed up in a crouching, defensive posture that allowed Carwin to attack without fear of counter punch. Carwin eventually knocked Lesnar to the ground and unleashed a pounding that came very close to knocking the champ out.

It was an understandable reaction. Carwin punches like a mule kicks. No one else had ever survived the first round with him. All of Lesnar's training – he worked on circling out of trouble and counter-attacking to gain some recovery time – went out the window.

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The bad news for all the contenders to Lesnar's belt is that he isn't likely to make the same mistake again. If there's one thing he's proven during his soaring career is that he's a quick study on making corrections

It means even as the competition remains considerable – Velasquez is both capable and formidable – we may be settling in for a long title reign here.

Lesnar faced myriad questions when he made the jump from professional wrestling to mixed martial arts. He begged UFC president Dana White to throw him in immediately against top competition.

Yes, Lesnar was a freak athlete, a former NCAA Division I wrestling champ and a guy athletic enough to nearly make the Minnesota Vikings despite minimal football training. Still, there was so much for him to learn. None of which he had the patience to do in the lower levels of MMA.

"It's no place for on-the-job training," White cautioned.

"I'm either good at this or I'm not," Lesnar said.

He's good at it. That much we know. The long-term question though was whether he viewed this as a quick, sideshow payday or an actual career he would dedicate his life to. Could he keep improving?

The obvious growth to his game, honed during endless sessions in a nondescript warehouse-turned-training-gym hard by the Alexandria, Minn. airport has answered that emphatically. He pays his staff top dollar. He brings in a slew of sparring partners. He reinvests his big earnings into getting better; his camp, he says, costs "six figures."

Not even a serious illness that sidelined him for a year has stopped his obvious progress. There are still plenty of fans who dislike Brock Lesnar. The one thing they can't question is his commitment to the sport.

He's gone from an inexperienced fighter that left himself vulnerable to a Frank Mir knee bar in his first UFC fight to a guy with good (and improving) submission defense. He's gone from a wrestling-first mountain of force that once smothered Heath Herring for three consecutive rounds but couldn't finish, to an all-around fighter capable of submitting Carwin.

There's no substitute for experience though and it stands to reason he'll grow from watching and rewatching his reaction to that first Carwin punch.

Velasquez offers a different, unique challenge. He's also a Division I wrestling standout who is in his prime at 28. Unbeaten (8-0), he's known for cardiovascular fitness and relentless work ethic – i.e. he may not punch as hard as Carwin, but he isn't going to punch himself out as quickly either.

For his part Lesnar has again taken the fight seriously and is said to already be at or even under the 265-pound weight limit. In the past, where strength and girth were more important, he was cutting weight until the final hours. He's clearly been working on his cardio.

Velasquez is a talent and he's certainly capable of beating Lesnar. Besides, this is MMA, where everyone gets caught eventually – even heavyweight legend Fedor Emelianenko lost his most recent match in the Strikeforce promotion.

That said, you can almost see something being built by Lesnar. He's shown a dedication to preparation. He's worked on his weaknesses. He's systematically answered every question about his game, all while maintaining the natural advantages he holds in size, strength and agility.

With each hurdle cleared, he seems to be picking up speed.