But after yet another SportsCenter-friendly performance, the Argentine-born middleweight champion just might be the best.
Better than Manny Pacquiao. Better than Floyd Mayweather.
"This was like Secretariat against just another thoroughbred," said Lou DiBella, who promotes Martinez (47-2-2, 26 KOs). "[Sergiy] Dzinziruk's a good fighter, but Sergio's a Hall of Fame fighter."
The 36-year-old Martinez was everybody's Fighter of the Year in 2010. He upset 2-to-1 favorite Kelly Pavlik for the middleweight title in April and nearly decapitated consensus pound-for-pounder Paul Williams in November.
And he showed no signs of slowing down Saturday at the MGM Grand at Foxwoods, sending Dzinziruk to the canvas no less than five times before referee Arthur Mercante Jr., put a stop to it at 1:43 of the eighth round.
DiBella made no secret about his aversion for this matchup, an opponent all but force-fed by HBO. Dzinziruk (37-1, 23 KOs) is virtually unknown in the United States, but many felt he was the best 154-pounder in the world. Not enough potential reward for the risk, DiBella reasoned, given Dzinziruk's pristine record and anemic Q score.
Indeed, at least theoretically, it was a showdown between the world's best middleweight and the best junior middleweight -- but Dzinziruk (still a title-holder at 154 pounds) spent most of the evening appearing out of his depth.
Martinez took the fight to Dzinziruk from the opening bell, dropping his hands to invite action and neutralizing the Ukranian's jab with a constant blur of activity. "Nullify his jab, nullify his punches," explained Martinez, who connected on 147-of-384 jabs, compared to 80-of-242 for Dzinziruk. "Little by little we did that."
Dzinziruk appeared confounded by the same squirrely, awkward style that gave Pavlik and Williams fits. Martinez amassed a lopsided lead on the scorecards by throwing and landing more punches, sending Dzinziruk to the canvas in the third and fourth rounds -- near the end of the latter on a vicious right-left-right-left combination.
After suffering a cut under his left eye in the seventh, Martinez finished strong with three knockdowns in the eighth -- each courtesy of his TNT-packed left hand. "I got a new wind," he said. "I was able to hit the gas and accelerate."
Martinez is a champion for another era. He doesn't blog. He doesn't tweet. He'll never deliver a juicy soundbite because he doesn't speak English, communicating through advisor Sampson Lewkowicz -- but his fists are multilingual.
Boxing's annals are filled with extraordinary backstories, but Martinez's path is remarkable even by fistic standards. He grew up in one of Argentina's toughest barrios, "a good kid in a really bad area," as DiBella puts it. A natural athete, he played as a striker for local club team Claypole during his teenage years.
But a funny thing happened on the way to the Bombonera. Martinez turned down a contract offer from Club Atlético Los Andes, a decision that perplexed many in a nation where fútbol is sacrosanct. (Imagine a Biletnikoff Award finalist pulling out of the NFL draft to sign up for the Golden Gloves.)
After a dalliance with cycling, Martinez was past 20 when he took up boxing. Credit DiBella for spotting the potential still there in the then-33-year-old a couple of years ago and pushing hard to re-energize his career.
And forgive the bellicose promoter if he's enjoying the payoff.
"I have never had a fighter like this, this guy is so good it's frightening," crowed DiBella, drenched to the bone with sweat during the post-fight presser. "He is a f---- beast. He is a beast. He does everything. He has speed, he has power, he has flair, he has style, he looks like a movie star and he fights like a beast."
Martinez's approach to the pound-for-pound question is more cerebal but no less passionate.
"It's a dream of mine, it obsesses me," said Martinez of the mythical title. "I will be pound-for-pound best.
"I want the best fighters in front of me. Mayweather, Pacquiao, I want them."
How he'll get them into the ring is the bigger question.
Don't hold your breath on Pacquiao, who's too small anyway. ("You think that Bob Arum's ever putting one of his guys in with this animal?" DiBella asked. "Never.")
Instead, Martinez could fight the best of what's left at 160 pounds. Felix Sturm jumps to mind.
That name might not move the needle among casual fans.
But if these highlight-reel showings keep up, Martinez's 2011 could prove even more rewarding than his 2010.